>While EE are basically held accountable by their employers

Licensed engineers are technically held accountable by their peers. The definition of a profession (versus just a job) is that professionals as a group are self-regulating. That is why e.g. doctors can be disciplined by their College, and lawyers can be disbarred by the legal society.

This is because Professional Engineering is actually a social process, not really a technical one. The work is technical, sure, but the reason we have Professional Engineers is because society realized long ago that letting any idiot build e.g. a bridge for public traffic is a bad idea.

Society, via legislation, grants professional licensing bodies special privileges in return for exerting control over the practising members of that profession.

The reason you don't see as many EEs (or aerospace) engineers with PEs is because the products that get produced in those specialties get certified in different ways. There's no bridge equivalent to the FCC, for example.