AFAIK there are not any USB modems in the new USB form factor. I haven't looked at what the adaptor chain looks like for "old USB and power at the same time" ... what does that look like ?
I think a single USB port on the new 12" is designed to be flawed. Apple knows these things last 5+ years so the second release of the 12" will have a second USB port on the other side and X% of folks will re-buy that to remove the original flaw. That's one way to combat hardware that lasts "too long".
> Remember, the keyboard abuts the side. The only areas where ports wouldn’t intersect with the keyboard are already taken: USB-C on the left, headphone jack on the right. Adding another USB-C port would require sacrificing the headphone jack. I doubt that will happen any time soon.
Apple's solution is to sell an adapter that lets you charge and use USB[2]. Not pretty, but fewer peripherals need wires these days. Heck, I use the MacBook as my primary dev machine and the only adapter I use is for my Yubikey.
1. http://geoff.greer.fm/2015/04/19/2015-macbook-review/
2. http://www.apple.com/shop/product/MJ1K2AM/A/usb-c-digital-av...
The keyboard appears to abut both sides equally ... so while there may be an internal component in the current iteration that takes up internal space, it's not the external footprint of the keyboard that is determining port or no-port.
Perhaps I am missing something ? Genuinely curious...
What I am saying is, the laptop (and the keyboard) are symmetrical left to right ... so if they can squeeze the port in on the left side, they should be able to squeeze an identical port in on the right side.
> Adding another USB-C port would require sacrificing the headphone jack.
Have you seen a MacBook in person? As soon as I did, I found this quite apparent.
Her biggest complaint is she sometimes forgets whether she has it in her bag or not because there is so little weight difference either way.