I HAVE EVIDENCE THAT THIS MIGHT NOT BE A BUG WITH TOWER UNITE SPECIFICALLY, BUT RATHER LINUX NOT CORRECTLY HANDLING HYBRID GRAPHIC SYSTEMS/USER ERROR.
I went through a journey with my own thread in the linux mint forums, as multiple games were causing system crashes for me. It was found that my system was not correctly utilizing my nvidia GPU (for reference, I also have integrated intel graphics on this laptop).
When my NVIDIA PRIME profile was set to “On-Demand” and I input this command in my system terminal
DRI_PRIME=1 glxinfo | grep "OpenGL renderer"
this would be the output:
glx: failed to create dri3 screen
failed to load driver: nouveau
OpenGL renderer string: Mesa Intel(R) UHD Graphics 630 (CFL GT2)
AFTER SWITCHING NVIDIA PRIME PROFILE TO PERFORMANCE MODE
the same input gave this output instead, the actual name of my nvidia gpu:
OpenGL renderer string: NVIDIA GeForce GTX 1650 with Max-Q Design/PCIe/SSE2
After this, I launch Tower Unite with DirectX 10 and these launch options (also still using proton version GE-Proton9-20)
__NV_PRIME_RENDER_OFFLOAD=1 __VK_LAYER_NV_optimus=NVIDIA_only __GLX_VENDOR_LIBRARY_NAME=nvidia gamemoderun mangohud %command% -notexturestreaming -useallavailablecores -nosplash
After this, I turned on workshop support in Tower Unite settings and joined two different Public Condos that were on Smooth Dirt map, hence these places had large builds including workshop items.
I NEVER CRASHED, AND MANGOHUD SHOWED THAT RAM USAGE NEVER EXCEEDED 12GB.
I would encourage OP to try out what I have if they also have a hybrid graphics system. If crashes stop occurring I would consider rescinding this bug report, as this might make these issues not a bug to Tower Unite itself.