What an unworldly remark. So, we should also not ban hard-drugs then?
In short, banning hard drugs is very very obviously a losing policy that serves only to enrich the world's worst people at the expense of everyone else.
Is this a serious question? Have you been asleep since 70s and are not aware on how the War on Drugs has been going?
The science tends to back these ideas up. Banning does not stop people from doing what they want.
Education and guard rails are always better than hard control.
In fact hard drugs are a pattern. There's no molecular fragment that makes something a hard drug. It's a label we apply based on patterns. Not design patterns though since drugs are discovered not designed.
In fact we do ban design patterns of drugs. There used to be an industry of slightly altering an illegal drug so it would have the same effect without being the banned chemical. They banned this by banning design patterns: no tryptamines with psychedelic effects, etc.