The only one of those things that a legacy USB connector is is orientation specific. They're not bulky. They're ubiquitous. Your mouse dies and you need a new one at 3 in the morning? Run over to the local 24 hour drug store, they'll be there. Need to send a large file to someone with a bad internet connection? Send it on a USB thumb drive, you know if they've got a computer they'll be able to open it. This is the new spec, but there's no reason to remove the legacy completely at this point. Just like most new car stereos still have a CD player even though most people get their music online now. It's ubiquitous. Everyone can, and will continue using it for a long time.