It's more likely the flurry of air tour accidents over the past couple of years. Two US underwriters ejected from the market after the NYC foot-selfie debacle. And the Hawaii incidents. And the Grand Canyon. Too many turbines crashing. A piston crashing doesn't cost them nearly as much. Soon there won't be anyone left to sell insurance at any price
No joke, I am seriously considering self-insuring the hull. Got to keep the liability, though. My insurance has gone up 30% in two years. I'm getting a very good rate, relatively speaking, but even so it's starting to be untenable.