Is this really a suprise
Let's face it, smartphones peaked in terms of usability for most people around 3 years ago. For most there is little point in upgrading unless the old phone has failed or suffered a catastrophic incident.
Apple got a boost this year in that it finally offered screen sizes that most iOS users thought they wanted, which I also bought into (well got "free" on a contract renewal), but I've since gone back to my 4S as it's just more convinient to use day to day.
Gone are the days where a new phone release sparks excitement, and a buying frenzy, as the incremental increases in processor speed and display resolution and size simply do not matter for the vast majority of users when their old phone is doing perfectly well.
Personally I think tech needs to, well, not slow down, but stop with producing new phones every year, and then give people something with a real bang 2 or 3 years down the line. The market is dead partly because of what I've previously mentioned, and that is that small incremental updates on a yearly basis are simply not enough to get people going.