>>713187694 (OP)It's mainly because he's not a publicity hound with le ebin quirky personality for people to latch on to.
He's smart enough to realize that as long as he's financially tied to Rockstar, it's a much better business strategy to have people associate games to the studio as a whole, rather than a single figure. I don't even want to think about how fucked Bethesda is from a marketing standpoint once Todd is retired, for example.