Taiwan is a ridiculously valuable tech asset. If China can seize control of TSMC, it’d be in an incredible position to make tons of money and potentially spy on the rest of the world. If the factories wind up inoperable for whatever reason… well, most of the chips they produce aren’t being sent to China anyway, so while it wouldn’t be good for anyone, it’d be much worse for the rest of the world. And with TSMC making efforts to offshore its talent and production anyway (even if it has been with very limited success so far), China wants to make a move sooner rather than later.