I am not sure I'd say I'm "against" it since broadly speaking I don't think it should be illegal, but I am against it in the sense that I really think that absolutely no one should be smoking weed. It's kind of an unearned opinion; I don't know anything about medicine or health or anything like that, but I hated what it would seemingly do to my friends in high school.

I'd have friends that would be more or less down to earth, start smoking weed, then start finding and watching videos of Alan Watts and Carl Sagan and convince themselves that they knew everything in the world about physics and philosophy, and they became utterly insufferable in the process, and whenever anything negative about weed was ever said, they would provide me a lecture about how weed is a cure to pretty much everything and how no one has ever had a negative effect from it ever in history.

I think there's been a huge over correction; there was so much bullshit about the dangers of weed that people started acting like it's some miraculous cure-all and ignoring actual issues.

This was such a visceral turn-off for me that I to this day have never used weed, and the idea of using it still kind of makes me viscerally annoyed. It's entirely possible that my friends were insufferable teenagers purely because teenagers can be insufferable, and that's not even unlikely, but the way I remember it is the weed making them annoying it. Not saying it's rational, just that memory and human brains are weird.