I am tempted to agree with most of what you say, but I think you have missed my point completely. China is a rational player and may prefer economic benefits of peace to horrors of war.That's private investment. If the CCP confiscates overseas investment during a war with the US, that's tough bananas for the companies that got involved. Washington is under no obligation to follow a foreign policy that benefits specific companies, nor is there any benefit to sacrificing Taiwan just to protect investment in China. Plus if American investments in China got confiscated, you can bet China wouldn't be allowed to cash in its US T-bonds.
Or to put it another way, if Washington's top concern was the security of overseas investments it would not be following its current foreign policy.