Hot take: it doesn't feel nice to have a change forced.
It should be the personal preference of the user to decide whether to use native or snap/flatpak. If native package manager decide to not support the package any longer it would be better to make user aware and stop maintaining app, than to install a snap package. This is a user's decision.
Also this can have far reaching consequences. Imagine you cannot use/install snaps on your machine due some reason, what now?