I’d also wondered about the long term effects of alcohol on Beck’s brain, but I do know a number of people personally who’d been very serious, hard core drinkers, then went the AA route, and are fine, normal, moral people today. So it could also be something else we don’t know about with him, but he is for sure nuts.
I knew someone who had Korean war PTSD. They were a heavy drinker for 10 years, an alcoholic for 15, got drunk 5 or 6 nights a week, but never missed a day of work. Then they started going to AA and never got drunk again. Five years later they had signs of early Alzheimers, got progressively worse over 10 years and died at age 75. The were being given a very good diet and ample vitamins, minerals and supplements. Although for their last 3 years they needed 24 hour supervision, they remained mobile and otherwise healthy until the last 1 to 6 months.