I'm somewhat experienced in mountaineering and have done several dangerous trips that have been incredible and memorable experiences. I would say, firstly, yes they have had a positive impact on my mental health, I have less fear, and the memory of those expeditions make me happy. But, as someone who tripped a lot in their 20s, I would say that trip experiences are just an entirely different "level" of experience to conventional experiences. There's something inherently transcendent in the way psychedelics alter your perception and inner world that you can't experience by mountaineering or extreme sports or what have you. You could argue that it's down to the chemistry, which would be partially true, but I don't think it's entirely mechanical, it's the quality of the experience that's different. I have never been pulled into inner space to meet fantastic beings of light who told me everything was going to be fine during a scrambling experience, nor have I dissolved my experience like a mist into complete, transcendent emptiness and calm at the peak of a mountain. Mostly, I've just been cold, hungry and tired up there :)