I would agree on that single point, however, Fentanyl is what I consider the 'end of the line' Opioid.
Two reasons: typically those of us who head down that path littered with corpses and regret have abused every other Opioid available and have an addiction so deep rooted we accept dying on the floor as acceptable.
The other: once Fentanyl gets a hold over you the odds of getting free are slim to nil whereas death is all but certain.
Typically I needed to double my dose every 4-6 weeks, the ability of Fent and its ilk to ruin your receptors is unrivalled - I couldn't get high on any other Opioid eventually. Such a progression almost inevitably offers up IV use as a way to slow it down, it seems sensible once those icy claws take hold - within a year I could shoot 5,000mcg and feel nothing, ~8mg/day was standard and even 12,000 mics administered directly provided but 4 hours of euphoria.
Walk away while you still can.