4 point belts should be standard on a sport sxs. I think those are extremely low numbers for injuries and deaths considering their popularity. 42% no seatbelt and 42% unknown? Can't fix stupid? Why does an off road vehicle need paved road rollover tests?
I don't see a need for intervention at this time. Just like everything in life, research your purchase, add safety gear according to your intended use and slowly learn the limits of your machine.
VERY easy to go on you tube and see what people are doing in these things. NO amount of safety gear or design changes will fix stupid.
Personal responsibility is out the window, sad really.