Its so mad that we have such a literal example of exactly what happens, due to prohibition, yet society refuses to see like for like. The mafia simply used the exact same routes to smuggle heroin. They didn’t disappear or die out, due to alcohol prohibition ending. They got into bed with the CIA, under operation gladio. What they did with crack wasn’t the first or the biggest example.
Like you said, you can’t people abusing substances. They remain illegal because somewhere some very powerful people are making too much money from them remaining so.