I was thinking about this earlier, and I thought of a reason why Ubi may have done this, under the assumption that the downgrade was intentional (because I refuse to believe it's because of technical reasons, and I think we'll hit/surpass the 2012 level of graphics before this generation is over).
I think this decision was made in the boardroom, under the assumption that the vast majority of the game's sales would be last-gen, PS360 versions, that the next-gen systems wouldn't have sold enough. In order for the last-genners to not feel that their version of the game has been "gimped" by comparison to next-gen, they made the decision that all versions would be more or less identical, a la AC4. Like AC4, it may have some small bells and whistles that the last-gen versions don't have, but it will still be the same experience overall, and the majority of their customers wouldn't feel "left out".
And then the unthinkable happened and the next-gen consoles are doing ridiculously well, software sales are higher than expected, and more and more gamers are looking ahead instead of back, either purchasing only next-gen or holding off on last-gen purchases for the inevitable upgrade down the way. And now Ubi looks like an idiot making a so-called "next-gen" game on parity with last-gen systems that no one wants to buy the game on.
If this theory is correct, then that's good news for The Division because there is no last-gen version. I don't expect it to look like what we've seen so far, because, you know... Ubisoft, but in theory it shouldn't look as bad as Watch Dogs.
Either that, or Ubi's programmers are just a bunch of dolts that need to have the definition of "next-gen" tattooed on their fucking foreheads.