I've taken lots of videos on the racetrack in my car, go-karting, snowboarding, motorcycle riding, scuba diving....
In addition to many of the things noted here (looks slow as hell due to wide-angle lens and the fact that you are, also, slow as hell)... the video editing is just a nightmare.
It's easy to capture a couple hours of footage of your hobby, but unless you ALSO have the hobby of WATCHING a couple hours of something you already did, the value is just not there.
I've watched almost none of the videos I've shot. Also, I'm still able to use my ancient Hero2. I thought of buying a newer model to get the "latest and greatest" as an impulse buy once; I can afford it, that's fine. I looked up a product matrix of the Session, Hero 5, Hero 6, black, silver, whatever products were available at the time. I just stared at the product matrix for awhile, gave up, and closed the browser window.
Honestly, if their product line had less overlap or fewer products or just.. made it easier to decide camera to buy, they'd have another $400 of my money.
shrug
They keep improving their products, but there are no real innovations or killer reasons to buy some new model. And they all basically work good enough.