I'd say that here in Finland, the decline in alcohol use has more to do with global trends, especially with the younger generations. The problem though is that there has not been any replacement for the social lubrication required here for people to attempt to be social. Purely based on my own experiences, people are less social, go out less, and therefore use less alcohol.
Feels as if the death of religion is followed by the death of bars, restaurants and other places to go out to in the evening, especially after Covid, leaving even fewer places to meet people.
It's true that people up here tend to get very drunk collectively as the evening drags on, which has always bothered me as somebody who doesn't drink alcohol... First everybody's very dry and awkward, then it's fun for an hour or so, and then things start getting over the top and pretty mental. Compared with central Europe, people don't slow down a few glasses in.
But all that is changing as it seems many people just stopped going out at all. So people might drink less alcohol, but I'm not sure that indicates an improvement of mental health or social coherence. The internet is making people lonelier.