There has been an explosion of “student driver” stickers here in the SF Bay Area. It’s completely voluntary, and most the vehicles appear to be driven by people in their 30s.

My son waited later to get his learning permit. I’ve met folks living it cities who never got driving licenses because there was no need. Could indeed be new drivers in their 30s.

Near me, it appears to be a decal parents are adding for the benefit of their high schoolers becoming new drivers.