Thank you for keeping MacOS and Linux in mind even though you don’t have the resources to fully support it.
I’m exclusively on Linux for both the VRChat client in VR (via GloriousEggroll’s Proton) and using the VRChat SDK (native), so knowing the team is aware of this minority and having a path forward (even if it’s more effort for us to set up) means a lot. 
Edit 2022-10-26: Basic commands seem to be working!
I followed the macOS instructions as suggested for Linux, also using sudo apt install dotnet6 as I’m on (K)Ubuntu 22.04. I’ll look into actually migrating soon™.
user@hostname:~$ vpm check project "$HOME/path/to/digitalfox-Avatar/"
[22:15:32 INF] Project is LegacySDK3Avatar