The built-in MacBook Pro display supports only 8-bit color**.
Attaching the NEC PA244UHD 4K display to the 2016 MacBook Pro confirms that the MacBook Pro drives the display at 60 Hz and 10-bit color*.
Portrait orientation (tall mode) works properly also, as do all the scaled resolution settings, although the default “Best for Display” is the wrong choice (too enlarged).
- The OWC Thunderbolt 2 Dock worked flawlessly with the display being detected immediately. It is on sale now for about $200.
- The Apple Thunderbolt 3 to Thunderbolt adapter did NOT work to drive the display. Unplugging and replugging and rebooting several times failed to ever detect the display. This is odd, because the same adapter was used to connect the OWC Thunderbolt 2 Dock.
So here we see one more hassle with the 2016 MacBook Pro: the Apple adapter does not function! However, since the OWC Thunderbolt 2 Dock (and future OWC Thunderbolt 3 Dock) offers many ports of several kinds, the smart move is to get both and use the Thunderbolt/MiniDisplayPort port on the Dock for the display, and the Apple adapter for any kind of external device other than a display.
* “30-Bit Color” means the 3 RGB channels at 10 bits each.
** “32-Bit Color” means 3 RGB channels plus alpha channel at 8 bits each.