> The idea that "the other culture" is some sort of inscrutable, mysterious entity that's completely alien to any kind of understanding or bridging by foreigners is a common talking point of authoritarian, nationalistic and/or warmongering rhetoric.

Damn straight! Beijing just wants to rile up Hong Kong into defeating themselves, presumably so someplace closer to Beijing becomes a more powerful trading post. No other party has a motive to turn HK against itself like this.