Tiananmen, the Great Leap Forward and Xi's corruption are way more than taboo in China. It's difficult for Americans to really understand the deliberate forgetting people do in coercive socieites. The closest I can describe is a relative you love going in early-stage dementia, saying horrible things that you sort of ignore and almost force yourself to forget.
(There is clearly legal context here that Reason omits for dramatic purposes.)
No, it doesn't. You're criticising in-group blindness. That's a problem. But it's mitigated by a competitive political system because each group has an incentive to call out the other's blinds spots. When this competition ceases, you get groupthink. The last major era of American groupthink was the W. Bush White House. It preceded America's greatest geopolitical disasters in decades.
Under Xi, China went from having quiet competition within the CCP to reigning in a state of groupthink. We don't know what moronic ideas Xi's friends hold because there is nobody in power with an incentive to call that sort of thing out.