> Due to some obscure legalities, Taiwan dropping the claim would amount to declaration of war
Your wording is a bit vague, but it sounds like you have it backwards. Taiwan's dropping of claims to the mainland may trigger a _Chinese_ declaration of war. That comes from certain interpretations of article 8 of the China's Anti-Secession law. Of course China doesn't actually have to declare war in this situation if they don't want to. They could always interpret it differently or they could simply ignore it (China's laws guarantee free speech after all and they certainly don't seem to have trouble getting around that).
Your wording is a bit vague, but it sounds like you have it backwards. Taiwan's dropping of claims to the mainland may trigger a _Chinese_ declaration of war. That comes from certain interpretations of article 8 of the China's Anti-Secession law. Of course China doesn't actually have to declare war in this situation if they don't want to. They could always interpret it differently or they could simply ignore it (China's laws guarantee free speech after all and they certainly don't seem to have trouble getting around that).