LL, the term Tech crew was used when there were several job descriptions on a flight deck. There used to be four, now there is only one-pilot.
Flight attendants used to be called air hostesses until the advent of males into the job. Now the job is called Flight attendant. We have moved on.
I don't see this as being revolutionary, or offensive. Airliners are now crewed by only pilots and Flight attendants. Why would people take offense. I never got a Tech crew license or studied to be a tech crew. The passengers call us pilots, not tech crew. They don't even know what the term means.
Ah-hem .... they're not passengers any more, they're 'customers' - which ****s me greatly.
I've got no problem with being called either a pilot or tech crew though.