What are you talking about. A. those systems don't make sure you partake responsibly, you even admit it yourself with the claim that legalization reduced popularity. and B. it's like so so so much better than alcohol or tobacco. Are you seriously suggesting that's where the bar should be for government regulation?

All drugs should be legal and we should have good programs to take care of you if you fuck up their use, it would be vastly cheaper and better for society than criminalization, especially if your claims about legalization reducing use are true.