Of course tecnically there is not differences between mining a vanity key and a randomn one. But there is a quite important psicological difference in how we consider a recognizable pattern against a random one; we tend to focus the pattern and give it more importance, and so we are more vulnerable to an impersonation attack.
Yes, NIP-05 is a solution with a good UX.
But so, why create a vanity address if is not showed/used?