lets not compare iphonex to Elon Musk's glass. I know nothing about glass, but, I trust the guy with a company called spaceX on his portfolio to make my glass right.
Metals arent particularly strong. Glass, plastics, etc are all stronger (yield strength). But boy are they ductile, and very tough. Iron can take, literally, an infinite number of loading cycle.
You can make ceramics, glass, etc better but the overall performance package of iron is very hard to beat.
If I were to dismiss SpaceX as 1950s technology with modern electronics and engine technology the soviets mastered in the 60s would you be annoyed?
So why dismiss the truck manufacturing industry? Semis are very thought out solutions for their domain.
the semi: 1. costs much more than an iphone, which we're to assume accounts for the expensive windshield. 2. the windshield can be as thick as your attitude.