Who do you think has control over TSMC factories if not the US?

China would wish it could take over Taiwan. In terms of local politics they could do it as they did with Hong Kong because the local population is pro China even more than Hong Kong.

But the US has so much armory stationed in the area that it looks as if they wouldn't let Taiwan go without a fight.
To this day TSMC ships most of its production directly to US controlled companies so in spite of being closer to china geographically the US is putting a big political war to keep it under control.