Its just super potent compared to other opioids/opiates using the same source material (opium). Its like 100x more potent than morphine and 50x heroin.

If you were slinging heroin and have a lab to make the stuff you just increased your production rate by that multiplier.

I’m sure there are some geopolitical PvP factors as the other commenter eluded to, but the economics of supply/demand were the enabler.