They’re already trying to maximize revenue and have maximized saturation of ads until their network becomes less sticky by people getting annoyed and not using it.

So you’re getting the same number of ads either way, even if Facebook can’t make more money off you.

That doesn’t really make sense. Publishers will already show you an ad every time doing so is profitable. They won’t show you an ad when it isn’t profitable.

Whatever opportunity you’re imagining where a publisher would a new ad once ads become less profitable, why wouldn’t they be showing a (more profitable) ad right now?