> I mean, why not just throw a few nukes in too?

Perhaps they'd want to keep the existing infrastructure for themselves? That's hard to do if you turn Taiwan into a pool of lava...

China is not ideologically able to turn Taiwan into a pool of lava. It's a Chinese province populated by Chinese people. They can take control, they can suppress it brutally, but anything that might suggest they value the general run of people living there less than they value the people living in Jiangsu is a nonstarter.

It's not as though the chip fabs just run themselves... biological warfare would destroy any community of humans.