What Hong Kong people are, they are the losers in the fight between China and the UK. The English ran away, leaving HK people as the losers.Maybe losers is too strong of a word, but that is what the Hong Kong people are, the conquered people. Historically they are called the losers of the conflict or what not.
Traditionally speaking, the losers complain. A lot.
Complaining usually does not work.
Those who complain will discover that that will lead no where. Only problem for them is when they discover all this complaining is useless, 20 years would have passed on by.
What did they think would happen to the "losers" of a conflict?
Best thing to do is try to make some effort to integrate into the new system. A very large portion of the Hong Kong population is practical enough to see that is the best way forward, for themselves and for Hong Kong.