Ok, but does Mathematica 12.1 at least install without any issues?
I believe 12.1 behaves in a similar manner to 12.2. My memory is a bit fuzzy here, it has been a while.
When I tried to launch Mathematica in Windows 10 WSL2 Ubuntu on Surface Pro X (without InsiderĀ“s Preview), it installed correctly from Shell (sh) script, but upon running there was an error, that I cannot run AMD64 architecture file on aarch64 architecture, although the build was for Linux.
The x64 emulator is for Windows executables. i.e., it does not apply to x64 binaries running in WSL.