Correct me if I'm wrong, but this #OptGreen project isn't talking specifically about Plasma, is it? They don't mention Plasma anywhere on the page they linked.
In any case, that's irrelevant, also, I don't doubt that KDE can't run at all under the specs you mentioned - that's not the issue. The question is, how much free/usable RAM do you actually have on that machine - let's say with no apps open first, and with then check again with Konsole + Dolphin + KWrite/Kate open? And for fun, fire up Konqueror as well and check again.
No you are not. Or you weren't. Allow me to quote your own post:
I’m talking about the “DE” part of KDE in general;
As the DE is Plasma, that is the part I am addressing. Now you are moving the goalposts. That said, I do not know what you mean when you refer to "the KDE project", as KDE encompasses many projects.
In any case, I don’t doubt that KDE can’t run at all under the specs you mentioned
So you don't doubt it is light. Of course if we pile on a bunch of apps, like we could throw in Blender open 50 times rendering 4K animations and I'm sure it will make the laptop run slow. But that would be because of Blender, not the DE.
However, for the sake of argument, I did try the three examples you quoted, Dolphin, Konsole and Kate, and as you can see in the aforementioned video, they are all also very light and worked perfectly simultaneously on the 2008 machine. I do not have Konqueror installed on that machine, as it is not considered an essential part of Plasma anymore and is not widely used.
You're arguing semantics and that's not the point I'm trying to argue here. Forget the term "Plasma". I don't really care about what the DE is branded as or what's in "Plasma" the software package. When I say "KDE", I mean the desktop + all the basic default/recommended apps that you'd see on a typical KDE installation, such as Dolphin, Konsole, Kate, Kalculator, Spectacle etc that's part of the KDE project. IDK whether the apps I've mentioned are considered part of "Plasma" or not, but again, that's not the point, I'm saying this is what I meant when I said "KDE" - and what most people would expect when they picture a "KDE" environment.
Anyways, I tested this myself on two identical VMs with 2GB RAM, one installed with Fedora 40 KDE, and another with Fedora 40 LXQt, both set to use X11 (because LXQt isn't Wayland ready yet), both updated and running the latest kernel 6.8.10-300.fc40. I logged into the DEs, opened only two terminal windows and nothing else, ran, and ran htop. The screenshot speaks for itself:
And when I tried disabling swap on both machines, the KDE machine was practically unusable, with only 53MB RAM remaining before it completely froze on me. Meanwhile, the LXQt one was still very much usable even without swap enabled.
I'd like to see you try running without swap and see how it fares. And if you think it's unfair disabling swap on a 2GB machine - try installing LXQt yourself, disable swap and see for yourself how much more usable it is compared to KDE.
And this is why I say KDE is bloated and not suitable for old machines.
Edit2: Here's a screenshot of the top 30 processes on my test systems, side-by-side:
Of the above, I calculated the usage of the top 10 processes specific to each respective DE, and you can see that KDE's memory usage is almost double that of LXQt. Had I counted all the DE-specific processes, it'd no doubt be a lot more than double.
You are moving the goalpost once again. First to be light the DE (i.e. Plasma) had to be light; then the DE had to be light, but not Plasma (?), but your redefinition of DE as in Plasma, plus a random set of apps (Dolphin, Konsole and Kate -- none of which are distributed with Plasma, by the way).
As that also proved to be light, now you are basing your argument on (a) a poll (?) and (b) that there is at least one desktop that is lighter and that does not need swap.
I am perfectly willing to admit the latter, mainly because it is true: there ARE DEs lighter than Plasma. But it is a strawman argument, as admitting that does not invalidate the statement that "Plasma is light" and "KDE'S software is not bloated".
I wish you would stick to one thing and argue in good faith. You seem incapable of that so, I'm done.
I'm not moving any goalposts. You're the one arguing about the semantics around "Plasma", and I keep saying that's irrelevant.
Refer back to my original comment which was, and I quote:
So, are there any plans to reduce the bloat in KDE, maybe even make a lightweight version (like LXQt) that’s suitable for older PCs with limited resources?
To clarify, here I was:
Referring to KDE + default apps that are part of a typical KDE installation
Stating that a typical KDE installation is bloated compared to a typical lightweight DE like LXQt
Saying with the intention that the "bloat" is RELATIVE, with respect to a older PC with limited resources
The ENTIRE point of my argument was the KDE isn't really ideal RELATIVELY, for older PCs with limited resources, and I'm using LXQt here are a reference.
In a subsequent test, here's a direct apples-to-apples(ish) component comparison:
Component
Process_KDE
RAM_KDE
Process_LXQt
RAM_LXQt
WM
kwin_x11
99
openbox
18
Terminal
konsole
76
qterminal
75
File Manager
Dolphin
135
pcmanfm-qt
80
File Archiver
ark
122
Lxqt-archiver
73
Text Editor
kwrite
121
featherpad
73
Image Viewer
gwenview
129
lximage-qt
76
Document Viewer
okular
128
qpdfview-qt6
51
Total
810
446
plasmashell was sitting at 250MB btw in this instance btw.
The numbers speak for themselves - no one in their right minds would consider KDE (or plasmashell, since you want to be pedantic) to be "light", in RELATION to an older PC with limited resources - which btw, was the premise of my entire argument. Of course KDE or plasmashell might be considered "light" on a modern system, but not an old PC with 2GB RAM. Whether something is considered light or bloated is always relative, and in this instance, it's obvious to anyone that KDE/plasmashell isn't "light".
Just for my 2 cents, I installed kde on an ancient HP elitebook, and while it was a tad slow to boot from disk due to the hard drive, the daily usage was honestly totally fine, and way better than the windows 7 it came with.
You are right that KDE is very light compared to windows, or even in general.