It's not too different from people testing the first hot air balloons, planes or helicopters (albeit much less risky, still).
Someone who has done a lot of skiing / parachuting can estimate well the risks of offtrack skiing and base jumping, plus lots of people have done it before and can inform you, plus the technology used (skiis / parachutes) have very long track records and known performance.
(Mountain biking doesn't seem to be in the same category, but whatever.)
> It's not too different from people testing the first hot air balloons, planes or helicopters (albeit much less risky, still).
Yes, good analogies.
It's not really unknown: it's really high and you better hope you don't mess up or you're dead/maimed. Sure here the “don't mess up“ happens mostly at design/build time instead of during the execution, but at the end of the day you're risking your life hoping you're not making a mistake. That's definitely not for everyone.
Well, that's also exactly what we are talking about here…
Also you're talking to someone who broke his own shoulder earlier this year while doing some very easy off-piste skiing earlier this year so I can absolutely assure you that danger is just a small mistake away even if you aren't doing insane stuff.