If, like me, you were born in the 70s you'll know that our parents didn't do this sort of thing into their adulthood...
I'm a touch younger (Xennial/Oregon Trail) with my parents being on the cusp of Boomers and GenX, and yes there were parents who did this sort of thing well into their own adulthood and into their children's adulthood, and for some of them now nearly into their grandchildren's adulthood.
Yes, some of them die young. I've already had a BIL (born in the early 70s) die in large part to drug-related conditions that caught up with him. Some don't and in there, there are those who are affected more than others. It's like the stories of those who smoked packs a day and made it 90 fine, there are a trail of other people who didn't. It's hard to say, some of it always going to be a gamble of benefits vs risks, though likely involves how consistently people have done this, what they're taking and the strength of it, and other lifestyle factors.
My father and I only talk by email and much of the time, even though he's 'cleaner' now in his 60s, I often struggle to figure out if he wrote them sober or intoxicated. He even admits himself now that he prioritized his friendships and pretty much worked as much as he did for those friends who played hard and now he lives the single life in a condo near friends possibly to facilitate this. He did crash and burn a bit in his 40s, but he's now still working in a high profile job in a major US corporation, so it's obviously not totally scrambled him.
I think there's a lot to be said for the view that drugs are wasted on the young.
I've heard that before, and I think we'll see a large difference between those who've been doing drugs since they were young throughout and those who take it up older which are far rarer talked about.
With reports that Gen Z is doing a lot less drinking and drug taking (and I know from my experience growing up with adults who took drugs, it did give me the feeling of it being an older person thing), I think it would be interesting if there was a cultural shift towards stronger drugs being more a 50+/empty nester sort of thing. With the writing and research on MDMA and microdosing as treatments, I can see the possibility of it even being at health weekends and events.