I have a dual monitor setup, with one 1440 and a ultra wide 2560x1080, and I don't have any issues with X11. It just works out of box. Something that I can't say of Wayland crashing every time that I try it.
Different scaling ratios in X11 do not work - period. You can define different ratios per monitor, but application windows will take the scale of the monitor they open on and never change.
Most distros are now on Wayland by default for a reason.
Gnome support is excellent.
Sway support is excellent.
KDE support is... not as excellent, but still pretty good at this point.
Ubuntu 21.04+ is on Wayland by default.
Fedora 35+ is running Wayland by default (minus KDE, where they default to x11 still, but ship a plasma-wayland session).
OpenSUSE Leap 15+ is running Wayland by default.
Debian Buster+ is running Wayland by default.
Garuda is running Wayland by default.
Manjaro Sway & Gnome are Wayland by default (again KDE is not - but the plasma-wayland session is included).
Basically - Wayland is not "the future" anymore. It's the "Right fucking now" across basically every major distro. Even KDE based distros are discussing moving to plasma-wayland by default at this point, since it's improved a lot in the last two years.
That said... if this is a shoddy attempt at a "gotcha" style question - Screen sharing and remote desktop are both supported.
Ex - for Gnome:
https://wiki.gnome.org/Projects/Mutter/RemoteDesktop
LibVNCServer for VNC support, FreeRDP for remote desktop protocol.
For KDE:
Which mostly just works as long as you have Pipewire and xdg-desktop-portal-kde installed (the base plasma-wayland session usually includes them)
This one is a bit less polished - some users still have problems with keyboard input, depending on the distro and other installed packages.
For Sway:
xdg-desktop-portal-wlr works just fine for screen sharing, and you can use https://github.com/any1/wayvnc for VNC access (including having a completely headless machine).
What I used to have on X was one model with 2x the pixel density as another. You either have things being tiny on one, and massive on the other or vice versa. What I did for a while was configure everything to be halfway between them so everything would be just _slightly_ off on both, but it was kind of horrible (and made the fonts look terrible).