PS: real case from a few months ago on Fedora.
PPS: oh, and guess what advice I got from the "helpful" widely advertised Linux community? "You have picked a bad distro and DE combo" (c) and "You have incorrect hw env for these distro and DE, why didn't you pick ubuntu/mate?" (c)
Ha! At one time I cursed those who threw this at me; now I know better, and throw it at others!
All joking aside, I really dislike Fedora and Gnome. It does have a lot of problems.
But, onto your problem: I would start at looking at the xserver logs, and ask about any recently changed settings/configs/options or updates/rollbacks. The logs are usually fairly good at telling you if something is !!!WRONG!!!.
Those are usually the most likely culprits, if the DE was working fine until all of a sudden it didn't anymore.
If it's a fresh install and right-off-the-bat it's buggy, then it's probably a HW issue (or the distro is terribad).
I would try xforwarding, and other built-in remote desktop options, to see if I could tinker around and get real-time feedback on how the display was looking.
On the other hand, if it's Wayland: I must yield, bow my head, wish you well, and withdraw from such an exercise.
For me Linux will probably never be "home ready" and will stay on servers and embeds where it is perfect and amazing.
It's much easier to diagnose + make changes to remedy the problem on Linux (if you know your way around).
Hell, even if you don't: the majority of the system (barring systemd) is fairly transparent, and you can readily find documentation/articles/blogs to better help you understand the problem -- and even fix it. Contrast this to Windows: I have no fucking clue how all the moving pieces come together. I just know that I can fuss about deep in settings/group policy/on the command line and roll the dice to see if any improvements are found.
Granted, most of the time it is the same for Linux, but it's much easier to simply SSH in, muck about, and so on, than it is to use TeamViewer (or go through the logistics headache of actually getting in front of the machine in question).