Yes, we were far less densely populated in 1957 so social distancing wasn't the problem as it is now.
We may have been less densely populated but I think more people proportionately travelled on public transport.
There were also 40 in a class and no thought of distancing - you either caught it or were lucky not to.
Everyone in my class caught it, in two waves, most in the first wave then the stragglers who thought they'd been lucky.
I don't, however, remember people congregating in the streets in large numbers and, quite frankly, people didn't seem to consume the amount of alcohol they do now which makes people less inhibited.
I'm not sure that Asian flu was as virulent as Spanish flu in 1917/20, and that came in separate waves, which is a worrying portent.