If legislation came against it, it would have it's value damaged. No one seems to use it for actual transactions. It uses enormous amounts of electricity.
Consider that the "proof of work" of fiat currencies is taxation + inflation (which wipes 1/2 of all your productivity), and you'll quickly realize that Bitcoin's PoW is considerably more efficient.
Also, Gold, Silver and other precious metals are more expensive to mine than Bitcoin, when measured on a store of value basis.