Actually, its not because of the high bandwidth of USB Type C since you can use the Continuum feature through Miracast.

It limited only on the Lumia 950 and Lumia 950 XL because both of them are using the Snapdragon 808 and 810 which actually support dual display mode. You can see it at the Snapdragon website (notice on the word "concurrent" that they use):

Snapdragon 810 :
Snapdragon 808 :
For comparison, here's how the Snapdragon 800 specs are stated :

Here's the full demo video :


The phone (Lumia 920) is just a dummy phone, as in it's not actually running the Continuum features a (probably just displaying screenshot), hell it's not even running Windows 10 Mobile.

At 22:30, if you notice on the icon on the status bar on that phone, you can see that those are the WP8 icons. In W10M, the "No sim card" icon has no white fill, just border and the plug on the charging icon are on the side, not center. In addition, the Continuum blue bar is all wrong. The blue background is supposed to also include the status bar, as seen in this video which shows a demo of an actual prototype running the Continuum feature (Skip to 6:30)

Also, in the official Microsoft's video of Continuum feature, you can see the phone have both on-screen and physical navigation bar (again, probably just showing a screenshot).

This post has been edited by Assassin's: Oct 16 2015, 06:35 PM

Just in case if someone wondering what will the Continuum feature video resolution output on these phones will be, according to the page below it is 1920x1080 and 1920x1200

http://www.microsoft.com/en-us/mobile/accessory/hd-500/