Ali was just a steaming pile of overly long mediocrity. I am a bit biased because I generally hate biopics, but still, I dont know how one of my favorite filmmakers could make such a turd about someone as great as Ali, but Mann pulled it off. The film seems to have no message or clear direction, and left me feeling nothing.
Vice I can objectively call a poor film, but I still love it for my personal bias' (Mann and Vice). If I was lukewarm on Mann and didn't love the show, then I would probably not have liked Vice anywheres near as much as I did.