Yes I know that Cuba, the DPRK, and China have their own distros, but they're pretty specific to the language and networks of those countries. I use linux because it's free and open source but I use one of those distros that is privately owned and I'm thinking of upgrading to something that is truly communally owned but also has good compatibility with software, especially scientific software. Any good recs please?
I think Debian has the best principles out of any distro. Debian follows a list of principles called Debian Free Software Guidelines (DFSG). You can read the principles and see if you like it.
The thing that I like the most about Debian is that the proprietary packages and FOSS packages are on different repositories. You can install Debian with no proprietary software and leave the proprietary repository disabled to have a completely FOSS system.
The Free / Non-Free demarcation is fairly well explored territory (and Debian is pretty solid on this front, despite falling short of FSF approval). Another thing that's worth consideration and doesn't get as much discussion is the organizational structure of a distribution.
Organizationally, there are roughly two types of Linux distributions. There are distributions which are created as a product or by-product of some company, who's goal is ultimately to make money (through support contracts or hardware sales typically). These are your Ubuntus, Red Hats, Fedoras, Pop_OSs, SteamOSes, etc. Then there are distributions which are maintained directly by a public collective who's sole purpose and raison d'être is the maintenance of the distribution. These are your Debians, Gentoos, ArchLinuxes, Guixs, etc.
As far as these collective organizations go, they vary a great deal in robustness. You could call a Github repository with a pair of maintainers and a dozen or so people reading the issue tracker an "organization." On the other end of this spectrum, there are distributions like Debian and Gentoo which have incredibly robust organizations with constitutions, bylaws, committees, elections, referenda, etc. Then there are a lot of distros developed on an ad-hoc basis somewhere in-between these two examples.
Having a charter and elections doesn't automatically make an institution good by any means, but governance structures like these have a big impact on the direction these distributions take, and what they are willing to compromise on. The ones which are organized publicly by members of the community rather than by the whims of some software company have done a good job keeping to their principles, and these distributions are among those of the greatest longevity.
I'll second Debian, but with the caveat that I don't deal much with scientific software. I'm assuming it should be fine given how prevalent Debian is. But I'd love to hear others speak to that for my own education as well.
I think Debian is "standard" enough to be a good choice for scientific applications. Debian was an early advocate of Reproducable Builds and has waged an arduous campaign towards ensuring as many of its packages are in compliance as possible. Determinism is a very appealing characteristic for scientists. There also is a Debian Science initiative with subgroups focused on maintaining packages for various disciplines. I haven't used Debian for anything really sciency, but it's renowned stability, long release cycle, and aforementioned initiatives make it a pretty good choice.
Another distribution which is worth consideration is Guix. Guix is quite a bit more complex to get started with, but it extends the idea of reproducible builds beyond individual packages, to encompass installation and configuration of all software on the system. The idea with Guix is that you put together a recipe for what software goes in your system and how it's configured, and from that recipe it will produce an identical system each time. This allows you to build up and tear down environments at will in a completely deterministic and automated fashion, rather than manually installing, configuring, and updating software as a sequence of manual, potentially error-prone actions. Guix is very similar to the (more popular) NixOS distribution, which would be a good choice for the same reasons, but for whatever reason I've seen a higher concentration of science people around Guix.
Personally I use Gentoo. Gentoo is probably not a great choice for scientific applications due to the sheer amount of variables introduced by Portage. None the less, it packages a number of nice programs for things like CAD, Finite Element Method, Computational Fluid Analysis, Astronomy, GIS, amateur radio, etc. So, you should be able to get going on just about any mature distribution. You just might take particular interest in Debian or Guix if you are primarily using your machine for scientific applications.
The users should own the means of computing. So choose Debian. The Debian Social Contract states:
We will be guided by the needs of our users and the free software community. We will place their interests first in our priorities.
Any commercial distros do not do this. I don't know if Arch or Gentoo have a written down charter or whatever, but they seem a lot less principled than Debian usually.
I use the immutable community variants of Fedora. Bazzite if you're a gamer, Bluefin or Aurora if not. Immutable is a whole other workflow, mainly in how you install packages (using flatpaks/brew or distrobox), but the system itself is essentially 0 maintenance because updates are automated and the OS rebuilt on reboot (while keeping your programs and user files). So its more stable than Arch nd you don't have packages that are 2 years out of date like on Debian. The only downside is updates take a lot of bandwidth if thats a problem for you. But they're the only distros I recommend to anybody now outside of Debian for servers.
The makers of Fedora, Red Hat, were acquired by IBM. So whilst there may be nothing wrong with the distro, they are part of your typical evil corpo. And I say this as a Fedora user
I can't contradict the fact that Fedora is owned by IBM and used as an upstream for their Red Hat software, it is slightly concerning but not inherently problematic. I'll at least say I personally have yet to experience any negatives for that fact, and I'll also add that it does like Debian, and defaults to a "free" software repository, you have to manually enable the non-free ones.
It probably isn't the "most socialist", but it's open source, absolutely prioritises open source fundamentally, and consequently it's controllable by the people the second a corp fucks it over (like most Linux distros). I don't think it's turned in service of evil (yet).
Linus Torvalds is not your ideological equal let's put it this way. Of course I get it, there's a lot to idolize there.
I'm not entirely sure from your posting what the word socialism means to you, but suffice to say that none of these software movements would ever be possible in environments like North Korea or China. A lot of the popularity Linux enjoys today is thanks to private entities like Canonical and Valve. Linus Torvalds has no disdain for such developments. He wants Linux to be "owned" by everyone because only if everyone can contribute will the codebase be the best it can be. This is purely pragmatic (apolitical) and a far cry from the views of Richard Stallman and the Free Software Foundation (which may be closer to your personal views).
Really this is what it boils down to. Linus Torvalds and The Linux Foundation are perfectly fine with private entities taking advantage of their software/code. It's what makes things like Android possible. And in the end everyone profits (from a code quality standpoint) because companies like Google then publish their modifications to what they have adopted.
However if Richard Stallman and the Free Software Foundation have their way none of this flies because software must never be profitable, it must always be developed purely to a societal benefit (sounds a lot more socialist if you ask me). Richard Stallman uses Trisquel btw. A Ubuntu derivative with zero tolerance towards any kind of proprietary software or firmware whatsoever.
I don't know if you'll see my comment following the removal of yours, but I suggest you look further into the history of fascism, the conditions that lead to it, and that socialists have consistently been the driving force of anti-fascism throughout history. To connect the two together because they both use "authority" is to be political illiterate and apply horseshoe theory.
Regarding authority, your use of it doesn't mean anything. All states wield authority - in liberal democracies and under fascism authority is used to enforce the class interests of the bourgeoisie. Look at how those who do not participate in capitalism will quickly lose their access to shelter and food and end up incarcerated as homelessness itself has become criminalised. Or the use of the national guard and overmilitarised police against the George Floyd and pro-Palestine protests.
In socialist states authority is used in the class interest of the proletariat against the bourgeoisie, intially for the effective redistribution of resources and then to prevent reactionary and bourgeoisie influence on society and government. You can compare the approval rates that citizens of socialist states such as the PRC have of their government to those of liberal democracies such as the US, and then look at statistics such as home ownership and poverty alleviation to understand which system functions better as a democracy acting in the interests of it's population.
If you want projects that are "communally owned", just avoid Ubuntu, SUSE, and RedHat distributions. Basically all other large distributions have a number of people working on them, and often even projects mostly run by one guy are happy to let others contribute.
Arch, Debian, Linux Mint, or anything recommended by the FSF.
GNU Guix seems to be your best bet if you're interested in software preservation and scientific development. It's written entirely in the GNU Guile language which is a dialect of Scheme, meaning that the project is easily portable to other operating systems. It also allows for the most freedom in distributing packages and maintaining reproducibility.
Are there any distros maintained by organizations outside the US orbit? Any US organization (Fedora, Debian, etc.) is required to comply with US sanctions and law. They're supposedly "free as in freedom" but they can't really be if they're under US jurisdiction.