IGNORE chat
It would be a convenient, inoffensive way for players to "rise above" anyone they thought was trash talking, spamming chat, or using abusive language. Player A doesn't have to deal with Player B anymore, and Player B gets to keep spouting nonsense unawares. And - as a bonus - we don't have to resort to creating a word filter and institutional censorship.
An additional nicety would be the ability to just type the first part of the name and have the game fill in or guess the rest, as long names and case sensitivity can be a hassle to reproduce.