By that logic you could argue that no one should be able to get compensated for their skills in an open marketplace.

That doesn't seem to track, to me. Maybe it would be better if the huge amounts of money generated by films were shared more equitably among the cast and crew?

The actors and athletes get paid a lot because someone is willing to pay that money, and they are willing because only a miniscule part of humankind has exceptional skills/talent. Most people are average in every way.

This assumes that these people are indeed genuinely exceptional, in some sort of superhuman way. Do you think the selection process for actors and athletes is both extensive and foolproof enough that you can guarantee that all and only the best and most talented people in the world get recognition? I know for sure that, for example, there are plenty of amazing musicians out there that haven't even crossed the radar of any music agencies. Surely the same is true of actors and athletes. No, the majority of actors working today are the result of nepotism and a narrow focus on what counts as talent - are the camera workers not talented? The people making the sets? The costume designers? Etc etc.