Large cap stocks weren't engineered for stability, but they're lower tail-risk than mid cap stocks, which are lower tail-risk than small cap stocks, and so on.

The same phenomenon has been broadly true across all markets over all of human history, and the underlying mechanism (heterogeneous flows) is well understood and rather intuitive.

Whether or not BTC adoption increases is not relevant to what I was saying. My only claim is that volatility will decrease if adoption increases, counter to the misplaced scepticism of the post I was replying to

If BTC adoption decreases instead, then volatility should increase, ceteris paribus.