What's "all fair" mean here?

Rebecca

By "all fair," he means that everything she said was legitimate and agreeable. "All" refers to the whole of what was mentioned, and "fair" means legitimate or agreeable. It's similar to saying "understandable" or "seems about right." Ex: A: He called you a liar and a cheat. B: All fair, honestly. Ex: Changing majors and moving cities seems all fair to me.