As I’ve said, it’s nothing really based on anything particularly deep, all the characters at some point have looked bad, acting petulantly and self-righteously and hypocritically and selfishly…and at other times being quite wonderful. I had no issues with Jack in last week’s ep, for example, he was the only one trying to be nice and do his job tbh, amid all these people being distracted by their personal problems.
But no, I tend to dislike him just because, to me, his worst comes so often, is so easily excused by the narrative and other characters, and is just coupled with a level of entitlement I found hard to tolerate, especially at the start, when most of my feelings about the show and characters were taking hold. It’s just personal taste.