Looking at Megvii
Despite only being 2.7% of China's GDP, Hong Kong continues to be absolutely central to China's high tech ambitions: providing a common law jurisdiction for money to transit through.
After the erosion of Hong Kong's freedoms guaranteed under "One Country Two Systems", there's been talk of the United States using the so-called "nuclear option": cutting Hong Kong off from all US dollar transactions. It's well within the ability of the US to do this, and it would completely crush the Hong Kong finance industry (and therefore cripple China for years). Yes, China would eventually recovery (with its Shanghai-based finance industry) and yes, this will also be painful for the US but it's a tool that the US may one day use against Hong Kong.
Deng Xiaoping designed the Hong Kong model as a pragmatic way for Taiwan to unify with the People's Republic of China. He spoke about giving Hong Kong another 50 years of One Country Two Systems if the first 50 years wasn't enough. The idea was that China would eventually become much more like Hong Kong, and that Taiwan could easily slot back in.
Sadly for Xi Jinping, the end of Hong Kong's freedoms means the end of any prospect of the totalitarian surveillance-state China ever unifying with open democratic Taiwan. The lack of Deng Xiaoping-style pragmatism will reverberate for decades to come.