I disagree. Your hypothesis is that if Marijuana is made legal, drug dealers would move to harder drugs.
My point, following your logic, is by making liquor illegal, drug dealers could move from hard drugs to bootlegging liquor. No more drug smuggling.
You still didn’t answer the simple question of whether or not you think it is a realistic consequence. Answer Yes, or no instead of changing the subject like a liberal who doesn’t want to answer.