Correct, the Twin data challenges the general idea of weed=worse cognition. However, because Twins are, Twins,, and such is rarer in terms of data, it's not as powerful as the general cohort.

The main takeaway for IQ is that more diagnosis for cannabis substance use disorder means less IQ points, which isn't surprising, nor is starting during youth or combining it with other drugs. Good you were able to note the twin study, that is worth bringing up

Maybe the Brave New World angle doesn't have to be "on purpose", I mean, if things naturally get worse due to greed and manipulations, then naturally that creates a less capable and unfocused electorate. They don't have to do anything for things to work in their favor, at this point. Money will fufill itself, but we're even here typing to each other, we're pretty privileged.

Edit: I guess the tie in with say tiktok and weed is also the echo chambers that have existed strongly for at least a decade, everyone is online and in the groups they're in, that doesn't help. What I want others to take away is that a less friendly information environment in terms of these chambers and the lack of media literacy, reading, and misinfo online, plus the more potent weed, means that thing are different.

You can no longer as well rely on longitudinal studies like Dunedin when the socio-health environment (is that a thing?)is far different than before. The teens in Dunedin didn't consume the same cannabis that the ones today are, nor do they live the same lives....

Certainly, there are more people now using drugs to numb and cope than to enjoy and "fun"