Letting China get away with dominating Hong Kong isn't going to do them 1 tiny iota of good long term, if they ever hope to make a stand, the time is now.
Luckily how? They’re going to lose. If they want freedom they’re going to have to leave China for it, emigrate. All the protest isn’t going to buy them victory. The CPC isn’t going to allow Hong Kong to publicly defeat it; that would be domestically politically disruptive. They’d rather abrogate the one country two systems agreement and just abolish the SAR’s freedoms altogether.