On the same day Tesla began carrying passengers in its steering-wheel-free Cybercab, federal regulators opened an investigation into whether the vehicle belongs on public roads at all. The launch marks the most uncompromising attempt yet to replace human control with algorithmic trust — a wager that the technology's readiness will outpace the law's caution. Wall Street's 6 percent rebuke of Tesla's stock suggests that confidence in that wager is far from universal, and that the distance between a bold debut and a sustainable future remains very much an open question.