It’s not that easy as just checking a box that says “enable decryption”. Not saying they can’t decrypt traffic, but it’s not trivial if you don’t have the private keys.
It is against the idea of the fediverse, but if you point a new user to a general purpose Lemmy instance and tell to sign up there, there isn’t much difference to reddit?
Default to the all communities feed, a single sign in page and they’re good to go.