I'm not sure this is a huge issue if you set up user expectations adequately. Just like JoeAsshole@gmail.com isn't the same account as JoeAsshole@hotmail.com.

I'm not sure this is a huge issue if you set up user expectations adequately. Just like JoeAsshole@gmail.com isn't the same account as JoeAsshole@hotmail.com. A workable alternative would be using a pubkey fingerprint with an mutable display name, but who wants to help their family sort that out?