Observe that "the world" will not be helping Taiwan. India won't. Russia won't. Brazil won't. Nigeria won't. Pakistan won't. Bangladesh won't. Nigeria won't. You get the drill. US will, and probably Europe too, but why assume that these will 1) be able to defeat China in a conventional war in its own back yard, and 2) will even try to do so?
The democratic countries will come together, the same ones that helped Ukraine; delete from that list authoritarian (democratic or not) countries, and democracies that are led by authoritarian dictator wanna-bes (so if Trump comes back he'd be conflicted, because he loves authoritarian power, but indicated his displeasure with China). Probably not Hungry. Russia doesn't matter if they aren't nuking you. India, there is the authoritarian bent the country it is on - non Hindu people aren't feeling so happy about their country. I'd think India will feel torn because they want to fight Pakistan freely but don't want to increase the power of China. Brazil is another partially fallen democratic country, wonder how that vote will turn out at the end of Oct.
There are two reasons those countries will help Taiwan - because they don't want authoritarian dictators to take over democracies, and because Ukraine reminded us all of the importance of stopping dictators - we can't wait for them to decide they have enough. It's over 80 years since the last time the world went through it, German and Japan were the original threats (with Italy and a few others), now it's China and Russia. The chip making part of Taiwan will all be decimated in the first few hours of a war (you thought that would be one of my reasons to intervene ;-)). It will be re-created bit after bombing it and damage and just losing power it will be hugely weakened, hurting both sides.
Ukraine showed how much more powerful the militaries of the western alliances are. I'm sure China will not be so weak and kleptocratically weakened as Russia was, but they haven't been in battles recently so they will need some ramping up to really organize. I'm sure China will be able to do major damage to navys trying to operate around Taiwan, sink a few us carriers. But the US and the other western countries are about a lot more and they can operate in countries around there.
China is a powerful country, they have brilliant engineers and scientists and that economy and a vast population. They are not to be under-estimated. The world must move forward to promote democracy and stop dictators.
