it's not a one-way street. Investors in China have returned many times their investment back to their domestic shareholders over the years. On the IP theft side - i have heard it described as the largest wealth transfer in history - i don't buy it. GM may very well have gone bankrupt if not for their China JVs and success of the Buick minivan there. It's all case by case. Foreign firms do nearly a trillion dollars a year of business in China that doesn't appear in the trade numbers because it is in China for China.
China has greatly benefitted, no question about it. But we should be happy that China has become wealthier during that period - a failed Chinese state is not something that we should wish for because of the catastrophic impact on the Chinese people.