As a middle aged guy who has used pot on and off for decades and no longer really enjoys the high, I'll say weed is good for two things:
Old man joint pains. Not headaches, broken bones, etc. But it nearly erases achy joint pain for me.
Being angry. I am much less angry in general when I'm smoking a bit every couple of days. That said, when I take a break I feel like my testosterone goes through the roof. I get more irritable and, TMI, I get a lot more spontaneous boners.
Weed is great for my anger and sleep. I’ve never found as good of a sleep medicine for someone who wakes up too early.
I also had debilitating anger in my teens and weed really helped calm that down. I’ve been off it for years at a time and I still can’t get past my anger without it.
That said my memory is shit