They use "Legalization" and "Decriminalization" interchangeably; they are not even close to the same thing.
Legalization mean you can buy it at a store.
Decriminalization means it's not a crime to own enough for personal use, trafficking is still generally illegal.
Given true choice, most people will avoid the highly addicting substances. Removing the stigma, more people will get help. Sort of an immediate, double-benefit on ending addiction issues
At this point it's pretty clear that the core of any plan has to be Controlled Supply and Housing First, but those are respectively divisive and expensive, so we won't get them as long as we live under the shadow of far-right movements growing powerful on our cities and provinces.