I'm not sure how Harm Reduction Treatment Clinics, including NPs in at Needle Exchanges, isn't part of a path towards a sane drug policy, decriminalization and legalization.
Are you familiar with the ideas behind Angela Davis' argument on how prisons are obsolete and can be practically/politically (policy wise) dismantled? Essentially, in a way it can be boiled down to using money spent on prisons and spend it where it's more necessary. Such as spending more appropriately on public health, education, employment services, adequate housing, etc. etc. E.G. the things the vast majority are truly in need of, the things most people are most in need of. Instead of spending the state's money primarily on things like LE, some on edu, a bit on pub health, and a tad on housing and even less on employment services, and one then here and there.
Spending more on real public health essentials wouldn't just create/support more exchanges and true Harm Reduction and evidence based forms of treatment, but it would also help to re-frame the "drug issue" from one narrowly limited to public safety towards one primarily focused on public health. For obvious reasons that would work to highlight the contradiction and problems inherent in the War on Drugs and prohibition, which would work to promote a more popular consensus on the need for legalization.
Needle exchanges alone won't do much though, true. But still can't see how spending more on them (as they're still largely illegal, let alone financially solvent) would be destructive in such a way. And apologies, horrible rendition of her argument on my part, but that's what I can do in 40 seconds off the top of my head. Check out the concise Are Prisons Obsolete? (Angela Davis).
Anyways, I do agree with you though. While I think direct forms of action are very important, the words and especially language (words and how we use and understand them) we use to discuss drugs, the war on drugs, etc. etc. is of vital importance. Such folks are doing a huge service, don't get me wrong. For right now, perhaps it's enough for them to speak up and speak out about the truth of what they and their cohorts are actually doing, in place of the usual "drugs are evil," "just say no," "Protect and Service" bullshit.
I'm not entirely inclined to believe that though. That it's enough. Even for now. But the more people doing what they can, the better off we'd all be.