This summary references several studies demonstrating pot use by youngsters decreases IQ and increases risk of certain mental health issues.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9255894/
There are also plenty of studies that show both those risks are significantly reduced in adults (25+).
Apparently you believe that pot is such an unmitigated good that one can't even make a joke about a truth that reflects poorly on it. I'm not interested in pursuing this further with a zealot.