You named people in several high-profile occupations who use marijuana, along with retired pensioners. They’ve already achieved some success in life. Lack of motivation has been an observed effect of regular marijuana use for quite some time. That’s more of a problem for those who haven’t yet gotten anywhere in life than it is for those who have. It’s much more of a problem for those who are not particularly motivated to begin with.
Well I guess it depends on how one defines success. Btw, the lack of motivation part is BS. There have been many wealthy individuals who've created lots of stuff, who claim to be regular users. So much for the motivation thing. I think like anything else, it depends on the individual.