Oh yeah, well MY lithografist
(what do you call the people who work in the lithography part of semiconductor manufacturing, anyway??) says they always use meters. It was microns, aka um or micrometers for a long time, but people got tired of saying things like .023 microns and finally started calling it 23 nm/nanometers when referring to the minimum feature size on an integrated circuit process node.
Electronics is a funny industry. It's mostly done in SI units, including meters for measuring everything about integrated chip sizing... the one stand-out exception is connectors/package sizing. 0.1 inch pitch for pin spacing is, or was, extremely common.
I think what the machinist friend might really mean is that most of his work comes dimensioned in inches, and it's therefore most convenient to do his work in inches too. Inches aren't inherently more easily divisible; what's really going on is that it's just a pain to do processing in one unit for a deliverable that's specified in the other unit. It might also be the case that most of the tools a machinist uses have their primary scale in inches, so there's a preference to keep the work in inches throughout.