I got slammed in another thread for trying to elucidate this point, but the parallel is the "economic anxiety" narrative behind increase in right-wing nationalism in liberal western countries. HK is no different, but as a city state this animosity is expressed as nativism against the influx of rich mainland Chinese immigrants buying up real estate and changing local culture.
When HK accounted for 1/4 of Chinese GDP, it had an industrial and service sector that supported a comfortable middle class life. The joke was that even HK taxi drivers could support multiple secret families on the mainland. Then mainland manufacturing made HK Detroit. HK also had a vibrant media/culture scene that has diminished in softpower. So you have a generation of kids who are doomed to live at home in cramped apartments with very few economic prospects watching themselves be economically, culturally, politically eclipsed by mainland "locusts" [1]. The same way alt-right dog whistles about immigration politics when there's perceived privilege change in the social order. HK is not a woke place. See drama over HK/Singapore beef, treatment and valuation of foreign domestic workers according to ethnic hierarchy. HKers want suffrage and autonomy, it's all very nice to western ears, but implicit in that desire is to keep HK for HKers because when China sends their people they're not sending their best.
>A row between Hongkongers and mainlanders is reaching boiling point after internet users raised more than HK$100,000 in less than a week to finance a full-page 'anti-locust' advertisement in a Chinese-language newspaper in the city.
...
>Mainlanders have already crossed our bottom line,' said Yung Jhon, who refused to disclose his real name. 'Why are mainland mothers flooding in to take up resources in public hospitals, getting our benefits and social welfare? Why do mainlanders ... refuse to follow our rules and order? We can't accept that.
This is not an isolated incident but popular sentiment that culminated from increasing mainland immigration to HK since handover. By law HK has to accept ~150 one-way permit holders from mainland per day under family reunification plan. That's 55k a year or ~1million mainland immigrants (in a city of 7 million) since handover. These mainland immigrants are disproportionately elderly and impoverished, "draining" HK social services. There's also extremely affluent mainlanders buying up property in HK, flaunting their wealth in shopping day trips. Spoiled, rich mainland Chinese kids whose parents were pig farmers a generation ago makes people's blood boil around the world. HK is no different.
