I've been skiing plenty of times. Runs where I'm at a high rate of speed and hitting countless variation changes (not moguls, just normal skiing) and my head is shaking so much that my vision is blurry. Landing a jump at best (when you absorb with your legs) is a 19G+ event. Every minor mistake in absorbing can tenfold increase that. Walking is not a relevant comparison.

We evolved to walk with a limited brain suspension that just wasn't adapted for 100kph wax shoe runs.