More people speed than smoke dope, and they're loosening regs on that.
Once you get about 30% of the population doing something, it's hard to tell them not to, politically.
IF this were to happen, it would probably be through insurance companies giving a discount for cars that did this. If the insurance market got crowded enough, eg you had to pay a super premium price for unlimited speed insurance, then you'd be "forced" to take it. Insuring some Teslas is already... interesting, with Tesla themselves subsidizing policies.