As far as I can tell, the decision to remove Mass Storage had two main drivers: * The removal of SD cards from mainstream phones * The use of ext4 as a main f

As far as I can tell, the decision to remove Mass Storage had two main drivers: * The removal of SD cards from mainstream phones * The use of ext4 as a main filesystem on a lot of phones. The removal of SD cards meant that you could no longer "unmount" part of the phone filesystem to present it as a mass storage device. The use of ext4 meant that many OSes had no idea how to mount the storage, even if you presented it as a block device. I'm not sure anyone will read this, but I think you could implement a FAT emulation layer over USB Gadget, at least enough to get car head-decks to play MP3s off the phone. If anyone wants to take a crack at this, please get in touch with me.