It is possible, but it is not a wayland limitation per-say but a compositor one (aka the wayland server), and I say “limitation” if the compositor doesn’t have multi-display option.
Technically wayland is not the issue:
If you look at your /run/user/[uid] (uid is probably 1000) you will see the wayland “displays” (socket here), usually named wayland-X. The /run[...] is usually set from $XDG_RUNTIME_DIR while the wayland socket to be used is set in the environment variable $WAYLAND_DISPLAY. So running an application in a 2nd session would just require setting the $WAYLAND_DISPLAY to an other value (that exists).
It seems that Sway is able to do this with the output command.





isn’t the whole case hot? Usually motherboard has sensors for monitoring the case temperature and control case fans. If the whole environment is above 45°C it makes everything hotter.
If you can check that an easy test would be to disable you CPU boost. I always do this anyway as boosting is a temporary way for a CPU to squeeze some extra performance at a huge energy/temperature cost. On my stress test this “only” get 10-15% more performance but without boost the CPU temperature never get above 50°C.
Because the CPU is not warming the case anyone everything is cooler, how much I don’t know though. Hopefully this could also reduce I/O on the SSD in general too but a cooler case is definitely better for every component.
The way to disable boosting depends on the CPU model as a starting point you can check https://wiki.archlinux.org/title/CPU_frequency_scaling#Configuring_frequency_boosting.