If they did I think there would actually be some quality of discussion, and it might be useful
I used to think this. (That isn't to say I've changed my mind. I'm just not convinced one way or the other.)
Another foreseeable outcome, relative to the time when the friend here was making the comment, is that it would lead to people being nastier in real life. Whether that's true or not (and I think that it might be), Twitter has turned out to be a cesspool, and it has shown us that people are willing to engage in all sorts of nastiness under their real name.