Where I live summers are a bit too warm and winters a bit too cold to make outdoor shopping joyful. Also, streets are noisy and full of aggressive drivers and the sidewalks are full of holes and broken tiles. So in the last few years this 1.5M population city has seen the construction of 10 shopping malls, most of which are actually really nice "gathering places" as you put it and most of which seem to thrive.
One advantage from most of the US malls that I have been to is that cars are parked under the malls, not around them, that most of the malls are built near subway or tram stops and that they somehow fit nicely into the surrounding architecture.
Often the malls are built in the city center and usually in a very nice quality. Usually the malls have one major supermarket chain in the basement that acts as an anchor store and usually they have a cinema and a food court in the top floor that offers not just the usual fast food but often also some decent food.
I really enjoy shopping in a mall and until someone fixes the problem of waiting and paying for delivery I don't see online shopping making malls obsolete.