If these protections work 100% and the kids are for sure not being manipulated and it doesn't take away from their education... And we're sure they don't 'not know better'. I'm not sure if we'd need that ban.
Let's say you're Harry Potter. Or Hermione Granger and you're 11 yo and you have people to make sure you don't suffer from working. I'm okay with that. And I think they got paid more than minimum wage. I didn't watch the documentary so I don't know if it worked out alright for them. But starring in movies reportedly is hard work.