[2022] i saw a 30mb update today, anyone knows what changed?

These small updates are pre-compiled GPU Shader downloads, caused by a Steam setting called "Shader Pre-Caching". Shaders help Vulkan and OpenGL games to load faster and improve framerate stability during gameplay.

If you wish to disable this option, just disable Shader Pre-Caching here:
Steam > Settings > Shader Pre-Caching

If you want to continue the discussion, please use this thread:
https://steamcommunity.com/app/892970/discussions/0/3112542578507166899/