There are other decentralized assets, too. What about gold or oil? By many standards, they're volatile markets, but compared to cryptocurrency they're very tame.

I think it's largely a matter of market liquidity. At higher prices, no one can push the price up with just a couple million dollars. Hopefully that, combined with bigger bid liquidity due to rising demand will help stabilize things.

I agree though, that these markets will always be less stable than lots of assets -- blue chips, bonds, commodities with inelastic supply and demand, etc.