I would caution against reading too much about CCP's resolve re Taiwan based on what happened inHK. Taiwan and HK are two very different issues. While both fall under "core interests", HK always had the stink of colonialism attached to it, not to mention the Basic Law, Mainland control of HK foreign policy, and other forms of integration with the Mainland. Taiwan, on the other hand, is a result of civil war between two Chinese political factions.

I believe this is important because the CCP had much more leverage and freedom to maneuver in HK, whereas it lacks these factors vis-a-vis Taiwan. What has also happened as a result of the HK move is that not only has Taiwanese resolve to counter the CCP increased substantially, other countries are now much more willing to call out Chinese actions. Perhaps the latter is also a function of the Trump administration, but I doubt that U.S. shift in policy alone would have caused European and other countries to call out China. CCP actions in HK served as a catalyst for some international cohesion against the CCP.

Furthermore, Taiwan has geopolitical implications for the U.S. as well as Japan and Korea, not to mention the ASEAN countries. HK, quite frankly, only served a financial purpose for Western businesses/financial institutions. The CCP rightfully concluded that as long it didn't interfere too much with Western ability to make money in HK, there would be no real repercussions for its actions. And they were right on the money.

I think a better indicator of CCP's resolve is their response to the recent naval crisis with the Philippines. They pushed and pushed, but backed away after some strong moves by the Filipinos and a declaration by the U.S. that certain actions would trigger treaty obligations.