@ashfurrow I think you're making the right choice for yourself and your users with regards to not transferring ownership, though I wonder if there's a middle-ground for future admins to consider:
Still delete the server but hand off the domain, so that people who wanted to trust a new admin could re-import themselves into the new owner's server. I guess impersonation could become an issue though if people squatted names used by previous participants.
@ocdtrekkie Thanks. Yeah, there are technical considerations there since fully-qualified masto usernames are both unique and unmutable.