Have you seen how much San Francisco and Seattle have improved with drug tolerant policies?
What makes you think that drug use has anything much to do at all with drug policy? People take drugs because society is shit, not because of the rule of law.
Society also becomes shit because people take drugs.
Now with that said, crack, meth and heroin are not "social drugs" and are not compatible with a healthy society. They are strongly addictive and cause permanent damage. You might disagree (and that's fine), but I don't see how making those legally available outside of addiction treatment facility will lead to favourable societal outcomes in any meaningful way.
Honestly, I don't think anyone can seriously claim it is anywhere near as bad as alcohol, other than in two regards: smoking isn't great for you (but that's a method problem, not a substance one) and the smell in public (which is a minor issue and, again, one that can be mitigated).
By any other measure - addiction, short-term and long-term harms, indirect harm to third-parties - alcohol is worse.