You're ok with meth, heroin, coke being legal and just being sold wherever/whenever. That's good for the community?
If an in-demand product is not legally produced and distributed it cannot be sensibly regulated.
Currently the substances you list are in significant demand and their production and distribution is 100% unregulated. The entire market is controlled by criminal cartels who actively promote their product to minor age children; settle business disputes with violence and murder; sell their product on street corners and from residential homes. Product purity is impossible to track resulting in increased disease and fatal overdoses.
Contrast this with legal amphetamines via Rx scripts, legal cocaine used in hospital settings and heroin dispensed in legal, controlled settings. Minors are not permitted access; fatal overdoses are extremely rare and none of the producers or sellers wage gun battles on the streets of our communities.
Drug use can be an extremely dubious personal choice. But insisting that commerical production and distribution be illegal is expressing defacto support for the criminal marketplace and all of the ancillary social damage connected.