I don't know about you, but close to 100% of everyone I know that have bought BTC (and other coins, for that matter) the past 5-10 years have done it in hopes of it going to the moon. The bitcoin maxis are at this point a fringe movement, a distant past, really.
If you put all your savings on index funds, there is some predictability and underlying assets to reason for. What is the best predictor for whether crypto goes up or down? How can you possibly predict what triggers its price, if there's little to none real-life usage?
Unless we see widespread adaption of some sort, for actual concrete applications, it is just going to be pure speculation.
But I agree on volatility - ETFs can certainly reduce volatility if there's enough growth.