My brother has been an addict for his entire adult life - for the last 20 years. His drug-of-choice started at cocaine, then crack, then heroin, and for the past few years has been exclusively fentanyl. So I have a lot of first-hand information perhaps biasing this point-of-view.
There was a big spike in deaths related to contaminated supply between 2015 and 2018 [1] which led to a lot of media coverage [2], which is completely understandable: many ordinary citizens ("normies" as my brother calls us) partaking in recreational drug use lost their lives during this period and so it created a lot of buzz.
You see though that there's another big spike starting 2020 [1], particularly starting April 2020 [3], which is not backed up by any growth in media coverage [2], suggesting that it did not have as much of an impact of "normies". And during this same period, there was a additional government assistance money available to addicts, beyond the normal welfare payments, which allowed addicts were able to purchase and use more drugs. Overdose deaths are 50% more likely in the days following receiving government assistance [4]. And this makes sense, when you're flush with cash, you can do more drugs. When you're an addict, you'll do as many drugs as you can. When those drugs are fentanyl, you're constantly teetering with death.
My brother claims to use a naloxone kit nearly every day on somebody - all people who are part of the community. And they're used on him very regularly too - even as an experienced addict, he overdoses regularly. In fact, he sometimes does this on purpose, because the high of an overdose is apparently second-to-none. But he says that he only does that when there's somebody else with him who can hit him with naloxone before he dies. This is not uncommon. I know a firefighter at the fire hall: regularly addicts will bash on their door and then immediately shoot up a huge dose, because they know the firefighters will rescue them.
That's not at all to say that a contaminated supply isn't the problem now: I'm just not convinced that it's the primary factor in deaths today.
[1] Page 3 of https://www2.gov.bc.ca/assets/gov/birth-adoption-death-marri...
[2] https://trends.google.com/trends/explore?date=all&geo=CA&q=f...
[3] Page 4 of https://www2.gov.bc.ca/assets/gov/birth-adoption-death-marri...
[4] Page 7 of https://www2.gov.bc.ca/assets/gov/birth-adoption-death-marri...