There was a wide range of views.
Older people (40+) tended either to moderately disapprove, or to be very tolerant. Younger people (25-35) were more extreme; they either strongly defended the place as you do, or were definitely against it. I haven't asked enough youths to be able to generalize. People from Copenhagen were often less tolerant than those from Funen or Jutland.
I think it depends when people last saw it, how often, and in what circumstances they visited.
Going on a wet November evening just to buy drugs isn't great, it feels dodgy. Warm summer evenings are nice -- just like everywhere else in Denmark. Pusher Street felt very tense a couple of years ago; I was approached by "security" for having a camera over my shoulder, but this summer it's very relaxed, since the stalls are open and no longer covered in camouflage netting.
That cannabis is legal-ish in some of the US isn't especially relevant. It makes as much sense to compare a Danish pub during American prohibition.
I visited Copenhagen last year and went to Christiana to see this vibe, greenness and artists. Instead I mainly saw teenagers drinking, and lots of litter. Another comment below mentioned that the legalization of drugs will hopefully bring Christiana back to what it used to be since it will not longer be the place to go get drugs.