Does your son understand your concerns? Does he understand the risk? Sometimes our kids can be so confident that that they aren't able to see those things, but if you've talked and explained and it's all sunken in ...
Let him take the risk if he feels ready for it.
Lol, I KNOW that is so much easier for me to say than for any of us to do. But we all know that we can't protect our kids forever. And sometimes you really have to let them jump off the ledge and see if the wings we've been giving them work.
It seems like a lot of AS find a real outlet in acting. I know very few people of any stripe will ever "make" it, but ... he's got to try. He'll always regret it if he doesn't. And if you hold him back, he'll resent you.
Just keep a back up safety net hidden and ready
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Mom to an amazing young adult AS son, plus an also amazing non-AS daughter. Most likely part of the "Broader Autism Phenotype" (some traits).