Hipfire accuracy is almost certainly worse now because that's the only reason to implement ADS in the first place. It's a way of forcing the player to choose between mobility and accuracy.
This is the point - people aren't complaining due to some aesthetic choice (although for me it actually is, I hate ADS as it covers too much stuff, I like being able to see my surroundings). You can still have hip fire have variable accuracy simply based on speed of movement.
ADS means hipfire will be almost useless in a competitive MP match. It risks making Halo 5 not feel like Halo.