When being late has become such a bad habit or perpetual sin among lots of selfish people that it is easier to apologize for making everybody wait for them than make the effort to being on time.
Saying sorry is conveniently easy and seldom comes with a penalty, but planning their time to be punctual is pretty hard for an unhealthy number of folks—for them, “no sorry, be on time” sounds like Greek to them.
A passive-aggressive response to reject a try-hard with unspecific plans, which actually means "I don't have time for you, but I have time for other people, so BYE."
Person 1: Hey I know we haven't seen each other in a while. Are you free to hang this week?