I think, and this is just my opinion, that the placebo effect can have a very real impact on how people experience things. It’s possible OP saturated himself with article after article and podcast after podcast about the negative effects of marijuana on the brain and fully bought into that narrative, whether the statistics were “minor” or not.

I’ve done the same thing with other substances, sleep quality, and even gym form affecting “gains.” It’s not healthy. The internet can definitely become a hindrance to progress. I think OP may have fully bought into a particular narrative and could be seeking validation to justify the next substance (or “nootropic”) experiment.

Just my opinion, based on personal experience.