Hello @joeky888, snap packages are meant to be self-contained and Proton is expected to directly interact with the host system's Steam install, which makes this request awkward to do sanely.
It would make more sense to package another flavor of wine with some of the extras found with Proton than to make a snap package of Proton itself, or for the entire Steam client to be in the environment, which is outside the scope of this issue tracker.
Update: use flatpak instead.
Proton is on flathub, for anyone interested you can install it via flatpak:
flatpak install flathub com.valvesoftware.Steam.CompatibilityTool.Proton
Or this command if you prefer the GE distribution:
flatpak install flathub com.valvesoftware.Steam.CompatibilityTool.Proton-GE
Nothing extracted yet.
Distributed via snap package https://snapcraft.io
It would be great if we can simply install it via command
sudo snap install protonon most Linux distros.