LeftCoaster hit the nail on the head. It's not how late the bars or lounges are open . . . it's what they are like after 2 am. I've been to clubs and lounges in cities that are cool, classy, and fun . . . giving you a "let's just stay here and have another drink while the trans chilly music flows over us" vibe. In other cities I've been out when it began to feel like a drunken brawl waiting to happen . . . not in an "isn't this exciting" way but more like "I think that guy over there has a knife and he and his friends are going to go after that man next to the girl who humiliated him a couple hours ago. But he so drunk he'll probably miss. I don't want to be anywhere near when it all goes to hell . . . let's get outta here."
From my exposure, more often than not Vancouver resembles the latter . . . much earlier than you'd expect. At times it's been fun, but I tend to make my way home earlier here because the scene tends to crash hard as the night wears on. Heck, my first experience out here involved seeing a girl drunk off her 🞵🞵🞵🞵 stumbling around the side of a building in Yaletown looking for a place to piss. I'm not even sure it was midnight yet.
Perhaps Vancouver isn't "ready" for the sophistication of late-night clubs? I know there are some nimby's, but I think it's the whooping and hollering and drunk driving on the streets that raises the concern, not the mere "presence" of a club. I was in London last week in the heart of Soho. People were out, bands were playing, and drinks were flowing. But no one was squealing and screaming, or howling like wolves as they headed home

. I could have stayed out til dawn with that crowd.
I have no doubt there are exceptions (which I'd love to hear). But that's my overall observation having lived here nearly two years.