Lack of mic and camera is colossally stupid. That stuff is standard fare for any handheld media device, be it phone, tablet, laptop, handheld gaming device or what have you.
Stuff like AR gaming, proper voice chat or video calls are all going to be thrown out over the 2$ savings on components? I seriously doubt it. There has to be a very specific reason as to why it doesn't have a camera. Perhaps the design is so unconventional that there's simply no logical place to put one. Maybe there's just barely any bezel around the screen.
No shit you wouldn't, because then you'd use an actual controller. There can be more than one control scheme.
Ever heard of headsets/earbuds with mics? Don't need a built in mic if you can just plug one in like a phone.