SteamVR runs great on Linux, unless for some oddly reason your favorite desktop on GNOME. Valve tested it on X11, KDE Plasma on Wayland (because duh) and wlroots (hyprland and friends) without problems.

There are tons of people happily running mixed DPI setups with -at least- wlroots based compositors (although first time setup can be a bit tricky, as these are built by hackers for hackers)