First of all, it is a dumb article.
If war broke out between China and Taiwan, TSMC, along with everything, will be destroyed by China, you cannot fight a war in Taiwan without widespread destruction, you cannot just spare TSMC or it's location because you want to keep it. It's either a peaceful reunion, or a full on war, there are no in between.
Second, TSMC will probably destroying the plant themselves if they were under hostile action. That's a strategic target for both side, pretty sure if war broke out that is not acceptable for the Taiwanese to have this target fallen into Chinese hand if that happens. Again, if this is an acceptable loss, then you won't be having a war.
And finally, the destruction of TSMC is not to held China hostage, it's to hold the west hostage. Taiwan will not transfer enough of their tech overseas to meet the supply of semi conductor, which mean if war broke out, there will be a chip shortage, and while this does not affect China, it will seriously affect the west, and hence the West would want to do everything they can to not have that happen, because when it happen, it will make the Chip shortage in 2020a child play, it will not just be you don't have enough PS5 or X-Boxes to go around, if that happen, everything runs on chip will be in shortage, from microwave to car. As long as this threat is there, the west will do anything to help Taiwan. This is what Taiwan is banking on.