It's hard to say. Weed most likely. MDMA and shrooms for medicinal purposes quite possibly. It really depends on what kind of people from the next generations take power once the boomers die off. It has to be obvious to a great many people now how ludicrous the War On Drugs is, for SO many reasons, but it's a bit of a sunk cost fallacy thing at this point, I feel. Considering how many countless lives have been ruined, people killed, governments funded and palms greased by said War, it's going to take a brave stance of political suicide to stand up and say hey this shit's fucked and wrong we're gonna fix it. Organised crime, big pharma and the liquor industry are absolutely all in bed with the governments to keep this shitshow rolling and they will not give it up without a fight.