DaVinci Resolve is much better than any open source NLE. Generally, most closed source media production software is better than their open source counterparts except Blender. Blender is incredible and it gives me hope that other open source software can be just as successful in the media industry.
No. It's free to use for the standard version with most features available for free. There's a paid "studio" license which unlocks all the features. Neither have their source code available for the public.
Lol you will find out its not when trying to install it on Linux. They only support CentOS, which actually doesnt exist anymore, and there is nearly no info about needed things. A Flatpak? No way. Appimage? Dream on.
I mean opening the install guide PDF file you got when you downloaded the installer from their website isn't that hard.
In most cases, you only need to left-click the installer anyways so you will probably not need it.
I just installed Resolve 18.5 on my Kubuntu laptop which worked very well except that Resolve apparently needs a dedicated GPU to work (at least on Linux, dunno about Windows).
A Flatpak would be welcome of course, but it's not needed.
Btw they support Rocky Linux, Centos 8 and RHEL 8 but the installation works well on presumably every distro.
For Rocky Linux, they even got an ISO for quick deployment and standardisation of the OS and Resolve in a company.