They couldn't even support Taiwan as a country politically because China bribed and bullied other countries to disagree with recognising Taiwan.
Hong Kongs a different case but shows how international support can be subdued by China.
Taiwan is a reality. Its growing military force supports this too. I don't think and I hope China would never invade.
I totally agree Taiwan is a country. But internationally this isn't often recognised and might give an invasion more clout. Ukraine/russia springs to mind as a similar scenario. Not the Ukraine weren't a country but that they didn't have enough international presence for anyone to properly back them up, when invaded.