China is a different situation
We don’t have any real ability to close down their economy . We rely on them for many of our necessities. Check your Covid test kits , for example .
Like Ukraine we didn’t have a treaty obligation to intervene for any invasion
Unlike Ukraine, Taiwan is really an historic part of China , the aboriginal folks were eliminated centuries ago.. So the claim by mainland China has legitimacy. The residents of Taiwan are Han Chinese.
China has 1.4 billion people . Taiwan? About 45 million.
It likely will be a Macau or Hong Kong situation where there is a one country, two systems resolutions. At least hopefully.
If China is intent on annexing Taiwan there is little anyone can or should do. China already has a problem with over population. Deaths from combat won’t dissuade them