The "epidemic" aspect refers mostly to the fact that fentanyl and fentanyl analogues are showing up in - literally - nearly all street heroin now (like drug testing services are showing 99 out of 100 samples containing fentanyl, and a large percentage are only fentanyl and no heroin), and even fake presses, and even in other drugs. Fentanyl has been a contaminant in several batches of cocaine in my town, recently a casual friend of mine died from it, and another guy I had met a few times but was a friend of my friend died the last time, from contaminated cocaine of all things. There were even fake gabapentin pills with fentanyl in them a while ago. It's crazy. Because of this, the rate of opioid overdoses has skyrocketed. There are without a doubt more opiate overdose deaths in recent times, by a lot. This is just a simple fact which you can see by looking at data that any source has gathered. I am not sure about the number of opioid addicted people, it seems like in the 90s there were also a whole lot of heroin addicts and it was a scourge of the population then, too. Certainly, though, there is a high rate of opiate addicts now, which is a problem. Some areas are hit especially hard, as someone else mentioned, Vancouver has a terrible problem, for example, that you couldn't possibly pretend didn't exist and wasn't much, much worse than at any other point, if you saw it.
As for your assertion that only a "small fraction" of opioid experimenters end up as addicts, I think that is a mistaken assumption that is in fact pretty dangerous to post on a harm reduction forum, where people come to find information and opinions when they are thinking about trying drugs, including opiates. I know for myself, I used opiates for years before I really realized I was an addict, and I spent 10 years of my life really badly addicted. I never went to IV use, because I hate needles, and I kept my life together, but my life became a living hell, and I'm a person who is good at keeping my shit together when inside I'm falling apart, so I'm lucky. And I still struggle. Of all the people I have known who got into opiates, some tried some hydrocodones a few times, maybe an oxy or two, and never developed an addiction, but the great majority of them have either had serious problems, or are dead. I literally don't know anyone who continued to use opioids casually for years, they either didn't use them much and stopped, or developed an addiction. And so many are dead, seriously. I've been doing drugs for decades, and more Bluelighters than I care to think about are dead now, most of them from opiate overdoses. Some of them were good friends. A few people I knew in high school ended up dead (from actual heroin back before the fentanyl days). One of my closest friends died a few years back (from fentanyl sold as heroin).
Give it time, and you'll see. Opiates have a place, for people in a lot of pain. If you had said that most people prescribed them for pain after procedures and such do not end up serious addicts, then I might agree with you. But experimental drug users are opening pandora's box with opiate experimentation. Most people I know in real life, and most Bluelighters who decide to try opiates and stick around for years so that we get to see how it progresses, end up with serious problems eventually, when the purpose of taking the opiates is to get high.
Of course some experimenters don't get addicted. But it has been my experience and observation that if you attempt to use opiates to get high, you will most likely develop a serious problem eventually. The two choices are to try them and stop, or try them and slowly increase rate of usage and dose over time. It is very difficult to maintain an equilibrium where you do not descend into addiction.