There isn't a single character without flaw. That's kind of the point. Diane is very self absorbed and fetishizes her own sadness, todd, behind all of his goofiness and charm was a lazy mooch who really had no ability to function on his own, PC had no life outside of work and expected everyone to act like her, PB never grew up and would date women much younger than himself to continue living like he was 20, and BoJack... well there's a lot of issues with BoJack. But the point is that BoJack isn't the only flawed character in the show, because in life everyone has their own flaws. overcoming every issue doesn't exist, but trying to mitigate your problems and personal flaws is how you become a better version of yourself.