Probably has a bit to do with it... I, for one was really happy with a great mid-range option that was by far the best value in each release... still on my N4, and not sure what I'm going to get as an upgrade.
I'm more or less fine with the nexus 5's camera (usually if an event is important to capture with great quality, someone else has a better camera already there), so I'd much rather the nexuses stick to the price point than go up in quality for a disproportionately larger increase in price.
