Controlled risks, bah humbug! If you think Everest is a controlled risk, do not go there, you are severely underestimating the risks and you would die.
Depends on how much money you spend. It's still not easy, but if you're in decent shape, spend the proper time acclimatizing, go during good weather, and pay for a boatload of sherpas to handle everything and guide you and only you, you'll probably survive. If you're in a group or only have one or two, the resources might not (probably won't) exist for them to do much if it happens where they're going to be severely taxed themselves... But 4 or 5 sherpas spending 100% of their time focused on keeping you (and themselves) alive can probably do it, and I'd call it a fairly controlled risk.
Now, whether or not you've really accomplished anything if you've had a team of people babysitting you to the top is another thing altogether.
As someone who has done three of four (not done Everest, but have done highest peak in continental US), I think I can fairly say you have a misconception of the risk with white water rafting. The risk of being thrown overboard is high, but the risk of death is much lower in my opinion than skydiving. Sure, a tandem jump is pretty safe, but progressing further is barely what I would call a “controlled” risk. With BASE jumping for example, it’s not really an “if” you’ll die, but rather a “when”. I’ve had many friends die (part of why I won’t do it myself) from doing BASE jumps.
I thought skydiving was just a series of safety procedures, whereas white water rafting is something challenging even to experts, especially at category 5.
> I thought skydiving was just a series of safety procedures
For basics, sure. Get into stacking, swooping, wing suit flying, CRW, XRW, BASE, etc and it gets extremely challenging to the point where dying is inevitable if you keep doing it.
I’ve been white water rafting maybe a dozen or more times in my life and have done CL5 / CL5+ rapids multiple times. I can assure you, no skydiving place I know of will let you get close to doing the activities I listed above with that little experience under your belt.
Edit:
As an example, when I worked at LinkedIn we as a team outing did Class IV+ rapids and most folks had zero prior experience. I think the “coaching” was like a 15min briefing before setting off, where as for sky diving you have to do an all day ground school class before jumping with two instructors holding onto you virtually the whole time. Even after being certified, you still typically have to go through the class again if you haven’t jumped recently.
I actually understand skydiving, bungee jumping, or climbing Everest, because they are controlled risks, but white water rafting seems very chaotic.