from the preview Dark Zone = best loot (Off-Topic)

by Xenos , Shores of Time, Friday, January 29, 2016, 16:30 (3306 days ago) @ Durandal

From the preview videos all the high end loot is in the Dark Zone, so you have to go in if you want to get high end gear. Similar to Challenge Mode Raids and ToO being the only option for 320 loot.

You could be right, but I haven't seen anything in the marketing suggesting it's the ONLY place you can get high end loot, just that it's A place to get high end loot.