The only anti-weed argument that I find indefensible is that the smell is annoying, because it is.
And perhaps potheads being fixated on weed means they're boring and unmotivated.
Public areas should be sober, clean, and peaceful because its courteous.
People should obviously not be addicts.
But, I don't really understand how you can get away from people wanting to smoke and drink recreationally. Same goes for coffee or tea or any predilection people have. What era was this not at least some part of human experience?
If we're going puritan why don't we ban fried foods, white bread, social media, gambling, and monetization of slop content while we're at it too if the entire goal is to "optimize and regulate" people. Go further, don't stop with these please.
That way we can really focus in on what life is about, which is grilled chicken, steamed vegetables, german industrial vehicle simulators, functional sex for the sake of procreation, and paying tax.
Obviously the real reason that prohibition didn't work is people didn't want to follow it, and enforcing it was impossible. So what exactly is the social contract for this kind of disagreement? "Fuck you, I'm doing it anyway" vs "Fuck you, you're going to prison"?