This is very much indeed about political correctness. There are three topics that China generally works very hard to stifle any talk about - sometimes dubbed “The three T’s - Tibet, Taiwan and Tienanmen.” (Hong Kong is also now joining that list.) They are, generally, the most politically-incorrect topics that one could talk about within China. Now, it’s not remarkable at all that the CCP would clamp down within its own borders, but when Western companies and governments and scholars bend over backwards to accommodate Beijing on this, that’s caving in to China-PC.