If I'm holding a phone I don't want a usb hub flapping around to plug in >1 device. More ports fit strictly more use cases. The only reason to limit phones to one port is so the manufacturer can save a few bucks.
Sure I can work around just about any problem, but I'm gonna say fuck you for making me.
EDIT: someone should fund me to make the ~11mm no speaker, no aux port, 2-4 usb-c port, dual sim, large/fast storage, beefy battery, rooted, juicy ass laptop killer that nobody knew they needed.
Now if we are going to talk about manufacturers saving a few bucks for the only reason of trying to be the bigger idiot we should take about the headphone jack.
You should be able to do that with an adapter. And if you use usb for headphones (which by the way is just ludicrous) you already live the dongle-life.
Though the motorola Z phones has what you want. Add the turbopower mod and you get the powerpack and an additional usb connection that can be used for charging (not sure if that mod allows that usb-port for anything else), leaving the original unused.
The Z-line is also the closest you can get to a replaceable battery so that is pretty neat as well.
