I'd debate the degree to which China opened its markets, but that's an aside -- I mostly agree with you in theory. But there's one nagging issue. Countless other developing nations that have done things such as open their markets and have had nowhere near the success to show for it that China has.

I think unforeseen consequences, both negative and positive, are a major part of how societies develop. We in general have nowhere near the foresight we like to image we do. And in particular, I'm more inclined to attribute China's success to their systems in large part because the only thing as large an outlier as their success is their governmental system. And the timing also fits quite well. If it's just e.g. open markets then it leaves you having to explain why China is thriving whereas most other developing nations following the WTO playbook have relatively little to show for it.