Linux’s need better multi-monitor support. It’s better than it’s ever been, but it’s still janky and giving black screens on tertiary screens at times.

Its more of a Desktop thing rather than Linux. If you use the right Desktop like Plasma then you have no issues at all.

I really don’t see any problems with Multi monitor, I actually have more issues with Windows 11 right now in terms of multiple Displays

I’ve been messing with this on and off for a few years now and I still haven’t seen support for multiple monitors running at different scaling levels (like running a 4K monitor at 125% alongside a 1080p monitor at 100%). This is a feature I use in Windows on one of my setups. I hope this gets some attention soon. I run Linux on most of my machines but this problem still gets in my way on others.
Then use Wayland, its there, its the default and KDE and Gnome should have each their own solution to this feature so you may compare them.