I think there's a good argument that they could do better. But there's also probably an argument that harder circuit breakers would result in posts like "AWS destroyed my business right when I was featured in the New York Times"--including things like deleting production data. I'm sort of sympathetic to the idea that AWS should have an experimental "rip it all down" option and kill all stateless services option but that adds another layer of complexity and introduces more edge cases.
Merely being on free tier is a signal that you do not want a $27,000 bill. There is no excuse for what AWS does here, and it is clear they use this clusterfuck as a revenue stream.
