Interesting predictions, but I'd like to see research providing a basis for them before I take risks with people's health and lives.
I agree that the current approach works very poorly; that doesn't mean any other approach is better. Sometimes what works poorly is still the best we can do, such as our approach to pancreatic cancer (though I don't think that's the case here).
Government restricts access to many things for safety reasons, from unsafe cars to prescription drugs to dodgy financial deals to highly enriched uranium. It's a simple formula, almost a slogan, to say 'legalize it and consumers will decide for themselves' (and in fairness maybe the parent isn't being formulaic in this case). In some cases that's true; in some cases consumers simply don't have that capability. In our business, IT security is a good example; consumers have no way to make a judgment or even know that it's working. It's the same for prescription drugs: Am I better? Is that due to the drug? The placebo effect? Natural progress? Maybe I'd be even better without the drug.
But that's all theory; before we mess with people's lives, we need evidence.