Less so now. I dive the Caribbean twice a year and the lionfish are down noticeably the last few years. Because they are a species of reef fish the only way to catch them is to hunt them. But mostly the local fish are learning that they are good eating if you know how to deal with the spines. Groupers, for instance, have learned to drive them toward the surface. When the lionfish runs out of room it turns to dive, the grouper strikes and takes him head-first. The venomous spines fold up and are harmless.
I’ve also seen Moray Eels and Barracuda take them. So while organized dive operations were necessary in past years it seems like Mother Nature is re-dressing the imbalance.
There are photos of sharks feeding on them.