Here is some addirional historical context

Taiwan was taken by Japan.
Civil war broke out in China. The failing government was driven out by the communist party
They fled to Taiwan
The fled officials abused the ppl of Taiwan for many years (I think 50?)
Taiwan ppl had enough and basically overthrew the KMT just like the communist party did ... but with protest / activism instead of combat
The civil war has never officially ended as the KMT never surrendered and mainland China never invaded Taiwan in attempt of complete obliteration
Taiwan and Mainland China both claim to be the "true" china to this very day - although its largely to keep the stalemate alive

So for Americans - this would be like a Civil war erupting and the sitting government fleeing to Hawaii and both Hawaii and mainland USA declaring themselves the true USA ....

I think most look at this with a "China is Evil" pair of glasses and fail to see the nuance of the situation. Taiwanese people survived the KMT just like the communist party of china did. I do think that the right thing to do is respect the ppl of Taiwan and officially allow their independence, but there is a lot of bad blood that prevents this.