Sounds like you are one of those extremely few safe and sane motorcycle drivers.
The reality is that this is what I see out on the road all the time both on the highway and on city streets.
https://www.youtube.com/watch?v=NVbiR_fQ38s
I don’t need to see that video to see what’s in it; and if anything, online video has exacerbated that problem by monetizing it! And yea, I think I’m relatively ‘sane’ out there, partially because I’m not 16, partially because 95% of my riding is through rush hour traffic, and partially because I’m a racing fan and know that there’s a good place to push to 10/10ths (ya know, where there’s no bus or tree or pothole or left-turners into traffic.) I don’t think I would’ve fared well if I’d started riding @ 16 in CA with mountain roads calling my name.
To invert the response, I don’t wear an action cam, but I think you’d be equally appalled at the actions people take while driving. In fact that’s one of the things fans of self-drive cars cite, although the incident at the root of this article has the human driver attempting a preventative action.