was this old (the google logo is the old one so i'm not sure) or was apple just uninformed?
you can have all sorts of multiple accounts in the control panel, mail and calendar all have on device log ons, you can update apps outside of the app store or use the google play store with your google account the same way you do with your apple account.
Given how they operate internally at the engineering level, probably just Apple being uninformed. The internal culture is total brainwash. Apple tech is the only tech. It is partly why they genuinely think they created technologies. They never stick their head out of the fruit to see what the world around them has, and they have a habit of buy, cheat, or steal to ensure their monopoly continues.
Maybe an interesting sociological experiment? How technology evolves in a cult versus outside the cult back in the real world?