Reply To: Why do people think they could “trust themselves” with smartphones?

I’ve heard in the name of the Steipler that the Sanhedrin would have
forbidden the use of cars because of the danger they pose to life.

I would like proof of this and even if its true, Even if jews dont drive, Non Jews do drive and there is still the danger of being hit by a car driven by a non-jews, the Sanhedrin has no power over them