Everything that is developed and added on to each new successive models will sooner or later come to a point where demand for something newer just plateau or slow way down. Why pay more when what you use functionally as a camera or whatever that product is fully satisfied? All product type will come to that point and unless something really revolutionary comes along to drive upgrading, demand will slow if not stop. Fanboy-ism will only go so far sometime especially if an economy is not doing well.
If we only see business numbers as something that needs to keep growing every year better then the less, you can not lost sight on where you have a market that is crazy or big enough to keep increasing those numbers. Sometime when you are already a big giant, being able to still attain the same figures, you might need to be happy that you are able to get to the same point. heheh.
I always said the most fundamental functions of a camera and quality has already been more then met digitally I feel a little less then 10 years back (give or take). After that, it is more hype marketing..etc that push the momentum, depending on other factors coming into play including improvement in camera function on smartphone and consumer being "fine" with what those IQ from smartphone can produce, why buy another item to lug around?
I think this is a time where it is not about selling more units but a focus on more specialized units or bespoke even. Even in a bad economy there are still people getting rich and normal folks would still shop but are more discerning on what they buy. Any product manager who thinks constant hyping and throwing in new bells and whistles for the sake of it need to re-look at their strategies for future growth.
Like me, I never buy on hype but base on function and purpose of use.