Will they really get paid less? The feeling I have now is that people are paid a lot not because of what they do, but because of the potential damage they can do in case they fucked up. E.g. CEOs, lawyers, etc. Moving some of the work to AI doesn't reduce the risk, so they should have the same pay in my mental model.

Plus C-level executives typically don't lower their pay, and IMO investors apparently don't care that much about their pay, I can't see a reason why their pay will be reduced (significantly).