Earlier quoted context omitted.
Wow that's cursed, never realized that's how it worked.
It's a good idea actually, but it's also really complex to get right. Early version of Android Auto could transfer over USB 2.0 instead of Bluetooth, which works, but it's not near as high bandwidth.
This sentence doesn't make much sense - Auto (and CarPlay) still work in wired mode over USB 2.0 if the head unit supports it. They never worked over Bluetooth.
(And they use less than 15Mbps so USB 2.0s 480MBps are more than enough)