UWP = Just buy the UWP Export and a MS Developer Account and you can use your own XB1 in Dev Mode to develop and publish to the UWP Store.
XB1 Console Export = You must apply to and be approved by MS onto the ID@XBox program, and get your game gets published on the "proper" XB1 Store.
There are some differences in the hardware available for a UWP program, although this has been vastly improved over time so the difference in available console resources isn't too big anymore between UWP and a "proper" XB1 game.