The CCP promise they won't use nukes on Taiwan.......huh?

Playing Devil's Advocate, for the PRC to use nuclear weapons (I abjure the word "nuke") would be self-defeating.

It would be in China's interest to take over the country as intact as possible; and also of course it would not to risk having its own radioactive fall-out back.

China is more likely to want to take over in other ways, such as blockading, isolation, subversion and interference.