I recall there being much animosity from those who'd been through the Airman Aircrew course at Finningley when the 'FC' brevet first appeared. The people who wore them had only minimal training (in those days) and were simply carrying out their ground skills in an airborne environment.
One 'FC' wearer appeared on our flight deck at some airshow static. The badge was quite new, so one of the groundcrew asked what it was. Whereupon our Air Eng quipped "He flies on the AWACS and fixes things - hence the 'Fuse Changer' badge".
Which was a little harsh, I guess?
I was fortunate enough to fly on a Voyager AAR sortie last September. Looking after our small group were a Voyager pilot and an air steward. Both looked very smart and both wore 'squadron' name badges with relevant insignia. For the pilot that meant 'Wings' and for the steward the 'CC' badge.
Pedants and keyboard SWOs will doubtless fulminate about dress standards, but I don't give a bugger. Both carried out their duties efficiently and were a delight to have met.