It is false that people generally consider themselves Chinese. Nearly 77% of people in Taiwan identify exclusively as Taiwanese: https://www.tpof.org/wp-content/uploads/2021/09/20210830-英文版...

It is also false that they desire peaceful reunification. The same source shows only 11% want to become part of China.

So the insistence you refer to is consistent with the will of the people of Taiwan.

No one in the Taiwanese government talks about claims to mainland PRC territory. Denouncing these previously made claims it would be a de facto (maybe even de jure?) move to independence and result in who knows what.