Plus the national security crackdown on demonstrators by Beijing, and how some organisers and demonstrators had to flee Hong Kong afterwards.
Anyway:
The situation has become so repressive that the UK government (the anti-migrant Tories even!) established a specific pathway for refugees from Hong Kong to come to the UK.
Not that that has gone well for all those refugees (because the Tories were incompetent as well as being anti-migrant, and the system isn't great.)
But I mean the jeopardy those protesters face is real enough that Britain did that.