Undisputed superpowers don't, but that is not China. China is a rising and secondary superpower and as such, tact and time-biding are useful tactics rather than blunt aggressive and machoism.
China should have already passed that points of tact and being on the defensive.
China is a rising superpower, but it will never become a fully risen one, if it doesn't reclaim Taiwan. It is the last step it needs to take to become a real global superpower in the eyes of the entire world.
China could grow 5% for another 50 years, but the rest of the world won't start treating it as a real, developed super-power unless it takes Taiwan under its control. They would always point their fingers to that.
I mean how embarrassing is it to have an US vassal that's blocking your whole entrance to the open sea, which is your territory by the UN, but at which you can't even park your ships or do nothing about while they entertain Lithuanian politicians who treat it as a real country. I mean from Lithuania to America, they treat it as a separate country nowadays de jure.