It's just absolutely false that "a vast majority of the locals hated the protests". See for example the contemporaneous polling done by Reuters below - 59% of the population supported the protests at the end of 2019 and 30% had participated [1]. There was also a District Council election in November 2019 in which the establishment (pro-government) parties were utterly wiped out [2].
To your second point, HK's housing situation is an unmitigated disaster that undoubtedly contributed to the overall atmosphere of discontent with the government, but it was not a proximate cause of the protests.
To your third point, merely going to a foreign government and asking them to put pressure on your home government would not remotely reach the bar for a treason conviction in the U.S. This idea that what Joshua Wong and Jimmy Lai did would be considered sedition or treason in Western democracies is something that everyone in China seems to "know" that just isn't so.
[1] https://www.reuters.com/article/world/exclusive-hong-kongers... [2] https://en.wikipedia.org/wiki/2019_Hong_Kong_local_elections