China has developed by going from Communist to Capitalist, yes. That said, they didn't use free trade policies to get there. Separately...I'm pretty sure that guy's name is ironic (like his tweet)...
All right, fair. I was wrong. It's not ironic, but I doubt he's actually a marxist/true communist, though he definitely seems to skew to that side of the age-old economic debate. In any case, he's right about China.