That's how I feel. Tripped for the first time at 15, have done stupid amounts of research drugs that I had probably no business getting into. I'd agree with you on the certain people thing. I kinda lied in the original post, one of my friends tripped way less than me and on safer drugs but my friend group and himself as well as believe that acid definitely changed him in a negative way. It was definitely over a couple years and he really should've put it down. He always handled the drugs so weirdly that half the time he'd trip you'd want to commit him to a psych ward. However, like you said it is really finicky. The person who I know did by far the most trips out of anyone I know (in variety, dose, and frequency) is to this day sharp as has ever been, one of the more intelligent people I know.

I personally don't feel like I've been affected at all by it. Even after having my worst trips I'd completely brush the shit off by the end of the peak while my other friend would be scrambled for a week. The only thing that does suck is that I've never had any life changing experiences in a good way either, even on highest doses and even on DMT my brain just brushes it off immediately after the peak.