The problem with that is sometimes the performer name is credited and sometimes the legal name, so you would end up with credits spread over two different artists.
I think MusicBrainz’ interface could be a lot better at exposing artist aliases (and lots of other information). If you want to add a credit for Sean Combs, Diddy does show up in the search, but without any information like a “legal name: Sean Combs” comment. And that makes it very confusing for editors who don’t know that Diddy and Sean Combs are the same person. And it would be nice if the search term you used is pre-filled in the credited as text box when you select an artist from the list, so you don’t have to change the artist credit back.
Likewise it would be nice if those search windows would be able to automatically show information on an entity based on relationships, like producer if that’s the artists most used credit, or member of if they have such a relationship.
But lack of developers means that we’ll have to live with the current situation for a while.