I think you're missing my point entirely. My point is that racing (not spectating) is fun, challenging and exciting, even when there's no danger. When there is danger it is, at best, a distraction from the racing that you're trying to do. Myrvold is the first racing enthusiast I've ever heard say he didn't find karting crazily fun and challenging, even in slow, safe karts.
And you know why? Because I have done my fair share of racing, both rallycross and karting - the race kart style. And guess what, I was the youngest ever member of the board in my local club. I was in a group that advocated for more safety when it came to track boundaries. At the same time, we worked against getting tarmac runoff, as the danger of spinning, retiring etc. would be lost. We also felt that it wouldn't train drivers as good as more demanding, and I guess in some situations, more dangerous run-offs would.
Thing is, I don't want things to be made deadly. But I want challenges, I want proper run-offs, with grass, sand, gravel and so on. I want kerbs that are higher, not these flat things we have now. I want to have that wow-feeling when cars are going side by side through corners in 250 km/h, and I know that one or both can spin out and retire on the spot. I want that challenge, for me, and for the "heroes" that have an insane salary (Hamiltons base-salary is more than half the budget for Manor...).
Indoor rental karts, there aren't any danger in it. There is precision, but it's slow, it's not an adrenaline rush. Maybe if that, and driving a car on the road is what you have done in your life - but coming from both racing karts and rallycross. It's boring, I do however enjoy the 2-3 hours rental karts races, because the winner instinct kicks back in, but the driving itself isn't any more fun. It's impossible to spin with the karts, it's nearly impossible to make a mistake with them, other than missing the line a bit.
The irony is that my racing career was stopped early, at the age of 17 due to a major head injury, brain hemorrhage, broken skull, damage to the left frontal lobe, I couldn't speak when I woke up etc. It was hell, and two years of training to get to where I am now. How did I get it? Well, I took a ride on my bike, and went to school. Or I tried, I didn't get there, I crashed with another cyclist. My biggest injury is racing was that I knocked by thumb once.
Danger for me doesn't have to be that you risk loosing your life or getting a serious injury. There is two kind of dangers, retirement and injury. The first danger is welcome. The second danger, should be there, but not pushed. To fulfill the first type of danger, you would need to remove tarmac run offs with gravel/grass. By doing that, you might in some situations increase the second danger. But that is for me, acceptable. Because without the first danger, there isn't that much of a wow-factor anymore. This is the reason why I like IndyCar more than F1 these days, if you look away from ovals, you still have many street tracks, with no runoff (even Monaco have now opened up many corners to have runoffs), and for the most part, all of the road courses have gravel, grass or sand runoffs as well. Seeing these drivers wheel to wheel, fighting over trackspace, without spinning and retiring is more impressive.
But, ye, sorry - to answer the question. Karting is challenging, and fun. Slow Rental Karts are boring
