Becos China do not want to take back a broken Taiwan. Peace reunification is still on the table.
US despite all the cheap move has never claim to abandon one China policy nor recognised Taiwan as independent country. They even send all the ex diplomats instead of real one just to please the western media and ignorant who think US still in control.
Time is on PRC China side
True but China needs to wait till around 2035 before it can be confident of taking back Taiwan by force if the US intervenes.