Were there any changes to keep only one version of the snap? The space for snaps is basically multiplied after few refreshes. Even with no heavy apps, extra copy of multipass + core + gnome eats 500Mb extra.
Is there a problem that snap revert can not revert to remote version in repository?
Because you need to have the snap revision available to revert to, and the snap store only allows downloading the most recent revision from a published channel/track, so if you don’t have that revision locally, you wouldn’t be able to revert to it.
It also doesn’t really match the use-case of snap revert, which is that if your snap got refreshed and it is broken, you would immediately notice and revert back to a working one, and then snap revert keeps you on that old revision until there is a revision available which is newer than the one you reverted away from.