Zamundaaa

Yes. The Mesa implementation for this stuff isn't merged yet. Once it is merged, the layer will be irrelevant.

Well, HDR works in Wine Wayland, and X11 can never do it without gamescope.

Yes, they do. They're just better at pretending they don't.

The last time the Dems held a primary was in 2008.

Why the fuck do people upvote this misinformation? They held primaries literally this year, which is information everyone can trivially look up

The real one? It was fine on Xorg though

When an app (in your case, Steam) uses X11 APIs to move the cursor, that of course works on Xorg, but Xwayland merely emulates it - so it moves the X11 pointer for X11 apps, but not the pointer from the Wayland compositor.

Some compositors allow Xwayland to request moving the real pointer instead of doing emulation, but River apparently doesn't.

I have some problems with X11 cursors and that's quite normal with Wayland obviously

It's not. There is no Wayland specific cursor format, it's all just images on disk, and the most widely used format hasn't changed away from Xcursors yet.

For example, my cursor can become invisible if my screen sleeps

That's either a compositor or driver bug, please report it (as I've never seen that on Plasma, to your compositor first).

Additional controllers that control mouse cursor don't control X11 cursor, however they still work, I just don't know where the cursor is unless it highlights something.

That's because it moves the X11 pointer but not the real one. A cursor theme can't change that.

and

Then you're using Xorg, not Wayland.

What problems do you have with per screen scaling on Wayland?

Stop using Xorg and your scaling problems are gone.

Debian

... is not something you should ever use on a desktop PC. Due to its eternally very outdated nature and not even shipping bugfix updates**** it is not a good fit for anything but servers.

Wayland, for some reason, couldn't handle 4 monitors, with one above the other three.

"Wayland" doesn't handle monitors at all. What (because of Debian, wildly outdated) desktop did you use?

Oh, and the biggest issue I had with Windows was copied straight into Linux. I want my (single) taskbar on a monitor that isn't my primary.

Not a Linux issue, but a problem with the desktop environment you chose. KDE Plasma allows you to configure panels in any way you want.

This is about dragging a tab out of or into a browser window, and letting the compositor know about it, so it can move and place the window accordingly. Apps don't get to place windows themselves.