The practical part of me says that having human game masters is a tough thing to scale, so you can’t have them present in every game, and so you have to make their influence marginal just to stop the experience being substantially worse when a human game master isn’t present.

I have a hard time believing that this could be economical over the long term. Unless the GMs are other players, and this is part of the game, they’ll need to be paid. Even an off-shored call center is going to be expensive.