Ah, I wasn't clear I see. Okay, my position is not that the representation is inaccurate but that given the representation it is not clear that it was the wrong decision. The post draws a line from Xuesen's deportation, to his actions in China, to China's present-day military aviation. But that is only a blunder if the counterfactual is that China would not have achieved that military aviation as fast. The picture drawn is that the Chinese had a sophisticated and intelligent organizational apparatus that knew to get key players and empower them to create successful organizations.
But the theory is that, knowing how to build this apparatus, it couldn't build an organization? That is not plausible. What is plausible is that a missile expert familiar with the rough organization of how to get to missiles and military aviation knew which parts of the organization need to be present. So primarily this was a knowledge transfer situation.
It would be much more convincing if a historical analysis landed on the idea that the Chinese were somehow blocked on progress on the technology. For instance, India received no Qian Xuesen and was a similarly positioned nation with similar aspirations, and had the disadvantage of reduced Soviet technology transfer. So we know from their success what the worst-case for indigenous development without a US-trained specialist (esp. one familiar in military organization development) is. Roughly 10 years across all, a couple of years for aviation, a decade plus for missile tech.
Having accelerated Chinese missile technology one decade (in hindsight), do we consider that trade reasonable? Integrating him after imprisonment would surely have been hard. So the counterfactual is that we don't do the prisoner exchange and find a way to hold him indefinitely? It seems to me that judging based on the outcome is likely saying one should have guessed heads because the coin landed heads and that this is a great blunder.