Look in /var/log/Xorg.0.log for Xorg errors.
Check if OpenGL is okay by running glxinfo (from the package mesa-utils) and checking in the first few lines for “direct rendering: Yes”.
Check if Vulkan is okay by running vulkaninfo (from the package vulkan-tools) and seeing… if it throws errors at you, I guess. There are probably some specific things you could look for but I’m not familiar enough with Vulkan yet.
You could sudo dmesg and read through looking for problems, but there might be a lot of noise to sift through. I’d start by piping it through grep -i nvidia to look for driver-specific stuff.
Might be worth running nvidia-settings and poking around to see if anything seems amiss. Not sure what you’d actually be looking for, but yeah.
Sometimes switching from linux and nvidia to linux-lts and nvidia-lts can help if the problem is in the kernel or driver. Remember to switch both of these at the same time, since drivers need to match the kernel.
You could also try switching from the nvidia drivers to nouveau. Might offer temporary relief and help narrow down where the problem is, at the expense of probably worse performance in heavy games. Ought to be fine for 2D gaming and general desktopping.
Trying a different window manager is always an option. Don’t know how much hassle that is when you use a full DE; I’ve always been the “just grab individual lightweight pieces and slap 'em together” sort so I don’t have any real experience with KDE. But yeah. Find out what the right way to change WM is for your system, then try swapping over to Openbox or something minimal like that and see what happens.
Related to WM/DE, it could be an issue with the compositor maybe. Look up whatever KDE’s compositor is and see if you can turn it off and run a different one?
I did not define the word magic. Society did that. My choice is to communicate effectively, which means largely respecting the established consensus on which words mean what. If you’d rather render yourself ineffectual by using your own personal alternate definitions for established words, that is your choice, but it’s not a choice that aligns with my or most other people’s priorities.
Besides, “magic” only has whimsy associated with it because we restrict it to fake things. If we’d been calling electricity “magic” all along, “magic” would be mundane and you’d be over here complaining that we don’t use a more whimsical term like “etherics” or “thaumaturgy” or “electricity.”
As for wonder… what the flippity floppity fuck are you even talking about? The scientific world is full of wonder. Wonder is what drives science in the first place, and it has nothing at all to do with terminology. If you look up at the night sky and are too distracted by vocabulary to feel wonder at the pretty lights shining across unfathomable temporal and spatial distances, well, that seems more like a deficiency in you than any sort of flaw in which arbitrary sounds and squiggles we’ve picked out to describe things with.