As for the age(s) of crashing riders ... there's a 24 year age span of folks under 40, so we riders older than 64 could weight the "over" group somewhat, depending on how one looks at it. I'm all of four years out of my hypothetic group and adding to that bunch.
There are a lot of careless young drivers who can't afford as big or as fast a bike as those of us who have worked and saved up. That said, I'm sure there as many overconfident seniors (carelss as often, I'm sure) who think we have the skills and strength we used to, and perhaps overplay experience we gained when drivers only had the road to pay attention to, not 'boomthumper' radios (my term) and cel phone social media.
I've owned and ridden for over 50 years, so have driven defensively for a long time. Whether driving or riding, I often see someone coming the opposite way veer over the centerline. Far more often than not, they are looking down as they pass me, my presence taking little precedence over their gadget.
Reasons I no longer ride at night include that so many kids go for those blue light covers and drive with their 'brights' on. Also, there are many who don't give a rip if oncoming traffic can see as long as they can with their brights on as well. Lastly, it seems like one of ten cars or trucks have a wildly mis-aimed headlight. If I were a LEO I'd be famous for ticketing them.
I live on a two lane road that is a 1 1/2 mi shortcut for many who don't live on it. You know the type, shaking fists and dirty looks that you didn't turn into your driveway at whatever speed they're all but pushing you from right behind your bumper.
It seems that nine of ten riders don't wear helmets, tho' the ones I notice wearing them are old guys on H-D's with quiet, OEM exhaust .. like myself.

I'd just as soon preserve my hearing and not mop the atmosphere with what hair the barber leaves me with. Risk assessment indeed. Some of us consider that
every time we 'saddle up'. Good ridin', guys. t o g