If you're like me and were / are experiencing some oddness on Linux running natively, I've painstakingly resolved the issues on my end. As usual, YMMV.
A little recap: I had to select "Legacy runtime 1.0" in order to play and for models to load correctly. However, the MOTD and lottery wouldn't load, and I was experiencing other oddness. Switching to Proton resolved some issues but caused other issues (as issues tend to do).
Enter an intense interrogation session with Google, which identifies the using the 64bit beta and patching CEF (Chromium Embedded Framework) solves many issues. Switching to 64 bit without the patch caused crashing, but once I patched CEF my experience was buttery smooth.

Next, go to compatibility and make sure you're on "Steam Linux Runtime 1.0 (scout)".

For a guide you can refer to their website here and/or the video below.
A little recap: I had to select "Legacy runtime 1.0" in order to play and for models to load correctly. However, the MOTD and lottery wouldn't load, and I was experiencing other oddness. Switching to Proton resolved some issues but caused other issues (as issues tend to do).
Enter an intense interrogation session with Google, which identifies the using the 64bit beta and patching CEF (Chromium Embedded Framework) solves many issues. Switching to 64 bit without the patch caused crashing, but once I patched CEF my experience was buttery smooth.
Disclaimer
As usual with these fixes aren't one size fits all, so you're mileage may vary. In my limited scope (myself) it made a huge difference. Feel free to report if you experienced improvement from this. I am not the author GModPatchTool and will not take responsibility if it bricks your system, kidnaps your family, or otherwise harms your experience.Switching to 64bit Beta
In the game properties, go to the "Betas" tab and click the "Beta Participation" dropdown, finally selecting the "x86-64 - Chromium + 64-bit binaries" option. Launch at least once.
Next, go to compatibility and make sure you're on "Steam Linux Runtime 1.0 (scout)".

Patching CEF (Chromium Embedded Framework)
You'll want to run the GModPatchTool found here: https://github.com/solsticegamestudios/GModCEFCodecFixFor a guide you can refer to their website here and/or the video below.