You can institute a lot of safety rules and equipment to make skiing, skate boarding, surfing non-lethal, and responsible parents and instructors do. That doesn’t stop some parents from not giving a shit, or some kids learning on their own without supervision or proper gear.
Nevertheless, it is possible to ski, snorkel etc. without risking your life.
Climbing Mt. Everest is a completly different category. Once you are in the death zone, or really, once you are beyond base camp, there is no possibility of rescue. Choppers can’t fly that high, and because of the height, even with oxygen, nobody can carry you down. You either walk/ climb on your own, or you die. That’s completly unlike skiing.
We don’t need kids to grow up to be “risk-takers”. We need them to grow up alive and able to evaluate risks, and take calculated risks, and have a long-term look.
Grown-ups who seek the thrill of risk-taking are not only a danger to themselves when doing sports by going higher and faster for the thrill, they tend to carry that reckless carelessness, that belief in their own invulnerability, into their other life, too, and end up making bad business decisions that harm many other people, or driving like crazy on the highway killing people.
As somebody who doesn’t participate in mountain climbing or extreme sports or things like that, I think you’re really over-extrapolating here. Some thrillseekers are idiots, others are mindful of what they’re doing. People who do crazy stuff without thinking about the consequences probably don’t give a lot to society and I expect many of them don’t last long. But people who accept serious risks and plan carefully to reduce the risks they do take (and minimize the harm to others if they screw up) can certainly contribute.
This is not, strictly speaking, entirely true. Heck, even crossing the quiet street in front of my house has a non-zero fatality risk. So I’m guessing you mean “reasonably safe” or “prudent” or something like that?