The majority of name changes on here are innocent, but some people unfortunately use them to role play a new identity for the purposes of trolling/trying to stir up drama.
I propose that all of an account's previous user names be listed on their profile (or at least user names within the past year). I know that with a bit of digging through post history, you can usually figure out who someone used to be, but this would make it much easier and more accessible.