Alcohol can be part of having a fun time, and having a fun time occasionally is good for your mental health (as opposed to the physical health of your brain, which appears to be what you're talking about).
This is certainly an opinion, but I think there are plenty of alternatives out there that can do a better job at enabling fun having without causing nearly as much bodily damage or functional impairment. We have a variety of choices in both the natural and pharmaceutical realms.