In the case of Taiwan, because there's not really a path to victory from straight up invasion that accomplishes anything really meaningful, unless Xi is down for his legacy to be 5 million deaths and the sudden burden of tens of millions of infrastructureless refugees that are apparently full throated PRC citizens now.
The PRC's only realistic hope is a soft power takeover which it seems mildly competent at progressing on. About to have a serious setback with the KMT recalls though.
I can only see China invading after SMIC has matched the capabilities of TSMC. China wouldn't need TSMC anymore and if the rest of the world' tech sectors collapse then sucks for them but not China.
If China ever succeeds in outmatching TSMC in both process and wafer output, Taiwan would have already lost as the big reason for defending them disappears.
The PRC's only realistic hope is a soft power takeover which it seems mildly competent at progressing on. About to have a serious setback with the KMT recalls though.