I can understand why he couldn't be hired as a licensed engineer because of that, but that doesn't make him not an engineer. He wasn't arguing over something that relies on local standards anyway. A second is a second regardless where you are.
FWIW, there are different types of seconds. Eg, Universal time seconds based on the Earth's rotation, and atomic clock seconds based on consensus. And leap smear seconds are variable length seconds to help merge one into the other. https://developers.google.com/time/smear