https://nebula.tv/videos/exploringhistory-bonus-does-hong-kongs-story-have-implications-for-taiwan
Bonus video, unscripted: does Hong Kong's Story Have Implications for Taiwan?
This is a Nebula-exclusive bonus video, so no YouTube link.
The gist is about how Taiwan's democracy was self-grown and has lasted a much longer time as an independent country than Hong Kong, whose democracy was thrust suddenly upon it just prior to hand-over in part as a cynical act to subvert Chinese rule. That's not to say that Hong Kongers didn't come to greatly appreciate their democracy in the 20 years before China broke the agreement and started cracking down on their freedoms, but just that the roots of their democracy are much shallower than Taiwan's, and therefore easier to uproot.
When they were first receiving Hong Kong back from the UK, some in China seemed to have been genuinely enthusiastic about "one country, two systems". And those people hoped to use the success of Hong Kong to show the Taiwanese how great it was, in order to bring Taiwan back into the fold. But it has become increasingly clear that the idea of one country two systems is dead, and Taiwanese opposition to reunification with China is at an all time high. There is now, thanks to China's aggressive crack-downs, no prospect of a peaceful reunification.
It's also really interesting that even China's historic claims over Taiwan are rather tenuous. There have been various points throughout history where central Chinese government has ruled over Taiwan, the longest of which was the Qing dynasty who held it from 1644ish until 1895. Then most recently shortly after WWII when the Republic of China held it until they lost mainland China.