I run everything in 1440 UW on CachyOS using my 9070. Some games dont handle the ultrawide very well, but, that was the same problem in windows.
I did get a 4k 120hz OLED TV for the home theater.
Currently, I have an old am4 PC running Ubuntu connected to it, but it just has a 1080ti, so its not even able to output at 4k 120.
I currently am able to use it at 4k/60hz, but its not really powerful enough for 4k with the 1080ti.
I do have another pc running cachyos with a 4070. Since the 4070 is more powerful, and it supports displayport 1.4a, i should be able to get a dp 1.4a to hdmi 2.1 adaptor and then drive a display at 4k 120hz..
Been playing around with steam's game streaming from one pc to another, and, having the more powerful GPU on the lower resolution monitor has held me back from experimenting a bit. I know there are ways around it (going back from wayland to X and setting up a fake/phantom display to get it to run stuff at 4k even though monitor does not support it, or creating a fake second display using one of those terminated dp or hdmi fake devices) .. but, anyhow, been very pleased with CachyOS here.
My close friend who cares more about stability/reliability, he gets anoyed when he pc wont boot or when the kernel gets broken or something, he switched to Fedora Silverblue, immutable makes a lot of sense for him, and he loves it.
I still have an ubuntu box, and a plain arch box,
my Slackware box is fully retired. Old 400mhz FSB northwoods celeron 1.8 that was replaced with a pentium 2.4 and went from 128mb ram to 4gb of ECC ram .... It was a dell poweredge deal from the hot deals forum back in the early 00s.