I agree. It's bragging about a bunch of things that either aren't part of KDE or aren't really gaming. It's like if MS made a "Gaming on Windows" page to advertise solitaire, minesweeper, pinball, and Steam.
I recently learned about Sysrq + f to kill running processes making the computer hang. Before finding about this I had to manually restart the PC via power button. I wonder if KDE should make it easier to enable this feature considering they have something to kill processes already but it’s less powerful than Sysrq.
I've been using it for a long time. I've personally found that there is essentially no impact on gaming performance--or if there is, it's so slight that it's totally negligible on midrange hardware, especially with feral gamemode. It might be more impactful on low spec PCs, I would assume, but I'm not sure of that. In my case, it's plenty lightweight and offers lots of customizability.
Can confirm. Used it early on (around Suse 7.3) and it took ages to compile and was bloated and buggy as heck. I switched to WindowMaker and never really looked back. Recently gave it a whirl on steamdeck and was pretty shocked at how polished and nice it is. If you haven’t given it a fair shake recently, you might be surprised.