Of course, at least many of the mechanical engineers at auto companies most likely do have PEs. It's not just civil engineers. It's mostly any engineer/engineering manager who signs off on drawings, test, etc. for regulators. When I worked on oil rig designs, I started down the path to getting a PE and it would have been expected had I stayed in that business.

That said, I'm sure there would be lots of complaints if software had a similar system given that it would likely come with specific educational and other specific requirements.