If you make something easier to access - either by reduced price, more contact, reduced social stigma - people will consume more of it, straight up.

Think of it like a social disease that has an R0/R1 that communicates itself much like COVID.

Kids how absolutely don't know anyone who's ever done Heroin, are unlikely to ever even have the thought, let alone, try to find out 'where on earth' to buy.

If you have a group of 3 kids in school who are starting to use, the likelihood that they 'infect' other students is very high.

We force people to isolate and take certain precautions when they threaten the community with COVID, why on earth we wouldn't do the same with heroin addiction?

And of course, it's not illegal to 'have' COVID and we are sympathetic to those that have it, so there's that as well ...

If you go out of your way to tell people that "drugs are bad and will kill you", and then those people find out you lied (see: every drug PSA ever), they may be inclined to seek proof, whereas they wouldn't have bothered if it weren't taboo

That is a very ridiculously wrong statement.

> Despite being illegal they are still so very easy to access in almost all countries

You apparently have a pretty wide definition of "Very easy". I wouldn't have the faintest clue how to lay my hands on some heroin. Yes, I might start asking around in the vicinity of nightclubs based on hearsay that party drugs are supposedly sold there and the dealers might know someone who sells heroin. That would require navigating some scary situations quite outside my comfort zone. That's a completely different level of availability than alcohol, of which there are shelves full in every supermarket and ads plastered all over telling me how it will make me hip and attractive.

> Legalising them would bring users/abusers into a more public sphere where it is far easier to access harm reduction and the state can provide it without legal complications

You don't need legalization for that, merely decriminalization of use and possession.

access isn't the only issue. There is a high risk with obtaining and possessing an illegal drug.

plus there's no guarantee anything you obtain is safe (mixed with shit) or the correct strength, so there's further risk in putting it in your veins.