I was answering the question about following someone in the other silo (not possible), not implying that the siloing makes data exfiltration absolutely impossible.

Note however that for the Chinese silo, they can just open the front door, whereas doing the same for the international version would endanger their profits. Profit is an incentive the CCP responds to very well. For the surveillance agencies, hacking the database is probably easier than setting up an official channel that too many people would have to know about and agree to.