There's a lot less emulation to do though because it's still running on x86 and the same graphics chips so the main emulation are the wine system calls and proton that handles the graphics calls. Running the same on the M* chips you're switching entire architectures and there's just not the history there to support the work. Proton drastically improved Linux gaming performance and it's largely from Steam investing money in it to avoid being locked into Windows if Microsoft ever tried to wall off the Windows garden to demand a cut of every store on the OS like Apple does with iOS and friends.
I don’t disagree with you but it’s still an emulation layer.
Sure but with all the work that's gone into it Proton is a VERY low friction emulation layer which is what matters more than the abstract idea of one being there or not. Proton works well enough it's largely invisible that you're running on an EMU layer outside of a few quirks like anticheat and more draconian DRM schemes not working.