Yes, the practical reality is that legislators would need to be convinced before anything changes. But shouldn't we try to establish some objective facts about the drug itself before deciding what to do about it?

That's where I'm coming from WRT effects, side-effects, addiction, etc. There is plenty of recent research -- granted, much of it conducted outside the U.S. -- showing that marijuana has fewer and milder direct health consequences compared to both tobacco and alcohol, addiction rates nowhere close to the other substances you compared to, intoxicating effects milder than alcohol, and numerous profound positive effects.

As long as people continue denying those facts, or (more commonly) denying that those facts have been sufficiently proven, it's not possible to discuss what laws are needed.