The plastics used for portable electronics will vary, but in general, you’ll see ABS, acrylics of different sorts, and smaller amounts of polyethylene, polypropylene (mostly in the internal components). Because of RoHS requirements, lead-free solder and other substitutes (mechanical connections) are employed. PVC has kind of fallen out of favor these days too.
The display panels will use glass internally, of course.
The beauty of small portable devices is that in the past, we actually had much larger devices. The raw materials required for an individual player is but a fraction of what used to be needed for a single device. No vacuum tubes and thorium emitters, oil filled transformers, big gobs of resin and such.
It’s a pity that electronic engineering feels a bit of a lost art in American universities, as manufacture all too often happens abroad. That equation is simple enough for the business majors to figure out.