I think a helpful contributing factor is that cigarettes are immediately annoying and unhealthy to the people around the user so you had the non users motivated to stop the users.
Being around a drunk person maybe also statistically unhealthy given the increased risk of falls, accidents, psychological damage?
I don't know, it's one of those things where I can't point which was the reason.
If I had to guess, maybe it was babies, kids and pregnant women. People don't get shitfaced around those categories but they had to endure passive smoke.
And the reduction in cigarette consumption is to be ascribed to that, plus society being less and less fond of stimulants due to risk averseness (this includes nictoine and also cocaine consumption which are both way down compared to the 70s-80s-90s)
The vast majority of people who drink aren't drunk, and not everyone who is drunk is unpleasant; everyone who smokes is putting out irritating smoke.