There was a lot of hysterical social media and agitation on behalf of a vocal minority inside Hong Kong. Even then, Hong Kong was already a police state under UK rule. It was one of the reasons Western libertarians loved the place (and it's spiritual twin Singapore).
The idea that a Chinese aligned government would need to extradite someone from Hong Kong to the mainland only makes sense if the person in question was a fugitive from the mainland hiding specifically in Hong Kong. Which would make about as much sense as an American fleeing the US criminal justice system in Guam or Puerto Rico.
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China has stated it would recognize not so much independence of Hong Kong but its self autonomy that allows it to run.
The Hong Kong political structure remains intact. The leadership has all rolled over to Chinese aligned bureaucrats. And the modern-day pro-Democracy protests are an echo of the same pro-Democracy movement that sprang up under British rule back in the 1980s.
This is where Western spin sells people on "Evil China" by neatly sweeping the history of these regions under the rug. You get an earful about China being anti-democratic, when it inherits an anti-democratic UK colony that it promises not to reform. You get an earful about abhorrent Chinese labor practices (the 996) that predate the hand-over and are exempted from mainland labor protections for the same reason. You read about an extradition from Hong Kong to Taiwan and get an earful of spin about how this threatens people in Hong Kong from Hong Kong. And then you read about a Hong Kong riot that kills a couple of Hong Kong cops, rephrased as Tiananmen Square 2.
All this on the back of Chinese reforms that prohibit crypto-scams, crack down on medical quackery, reform predatory loans in the housing market, and dramatically improve labor and environmental standards nationwide, which just so happen to rub a bunch of MAGA-aligned US mega-corps the wrong way.