I'm a Yank, on your side in this. However, I remember the first morning I ever woke up in China, as a tourist in 2000. My first thought was "Why don't they just take back Taiwan?" I was impressed with their industrial power. They have nearly inexhaustible natural resources and soldiers to throw at Taiwan, which is right on their doorstep. The answer is that China calculates a benefit from the status quo. Whether it's in banking or technology or something else, I'm not qualified to say.
AUKUS is a step in the right direction, but holding China at bay when they decide to take Taiwan is gonna be tough despite the alliance, due to the resources needed to fight that war from a distance. I hope it doesn't involve nukes.