The previous Actives have all received major OS updates, so I have no doubts that the S7 Active will get Nougat, it will just probably get it a few months after the S7 on AT&T does.
October for the S7 and S7 Edge so I foresee the Active getting it in 2017. It's exclusive to AT&T and they'll beat it to death with their bloatware before releasing the update.
I have nougat on my Nexus 6P and there is no new features that My S7 Active did not already have. Google is playing catch up to Samsung in the features game.