Or maybe it's that people feel that Apple no longer listens so much to customer wishes as they used to or think that Apple should listen more.
Previous updates brought benefits to more people in their daily live like the introduction of 3G, then HSDPA, then LTE on some bands and then a great number of more LTE bands. And this year? LTE Advanced. That maybe nice to have but is it a real benefit for the average user?
Look at some of the wishes for this year: increased baseline storage, updated 4 inch model and lager battery or rather longer battery life.
The first two didn't happen. The battery got reduced instead, but there is "hope" that a new version of iOS and new components will deliver the same battery life.
3D Touch may bring new features but some might asked, if the same might not have been achieved with a longer press on the screen instead of a "deeper" press. And that longer press could have been easily brought to older iPhones.
And if your living outside the US some new features are not supported. Wifi calling or take Apple Pay. As far as I know both are not supported in Germany and will probably not in the next two years.
And there might be people who see the reduced price of 64GB and 128GB as an increase for the 16GB version.
For people outside the US the price might have increased. In Germany the baseline 6S is now 6% more expensive compared to the baseline 6 last year.