It makes me laugh always - well almost laugh - any time I hear these marketing terms for plastic. Call it polycarbonate or "engineering plastic". It's plastic. It's cheap. It breaks and gets creaky and flimsy. I don't want it. I don't see why I should pay more to get less.
Call it plastic if you want, but to a materials engineer there's a world of difference. They don't use the same plastic as the $2 toys from china, this is real material with a lot of research behind it. In a lot of cases, it's stronger, lighter, tougher, and
less flimsy and malleable than aluminium, and it's not much cheaper once you take high r&d costs into account (it only gets cheaper over mass-production, hence it's mostly used on high-volume units). Stop giving me cheap, easy-to-produce aluminium.
(that said, my mum's Asahi Pentax Takumars from 1967 are very nice. But that's more a function of hand-manufacturing than the material they're made of. Either way, I'd rather the R&D cost of my lenses go at least 90% into the optics side)