Like dont they know that ultimately both koreans and chinese would move on if there was a definitive apology

It's not so much the lack of an apology. The japanese have apologized multiple times. The problem is that they apologize but then do some dumb shit to contradict said apology like visiting Yasukuni shrine or engaging in attrocity denial.

It's like an abuser apologizing to their victim, then days later they're bragging to their friends about how they "put that bitch in her place".