I requested the actual report from Argus ~2 weeks ago, they never emailed a copy. I just tried again a moment ago, no email. Because of that, hard to analyze the details.
That chart is weird. I am not sure what it is measuring. Sales? Public opinion? And it's not even measuring the actual levels of either, just the change in it from the previous year.
It's an interesting claim but not sure how to analyze given the limited information provided and unclear presentation.
I'll approach this issue from anohter point of view, ancedotes. I have done a lot of ad hoc evaluation of various IoT systems over the past 5 years.
My findings so far point a red finger at most of the 900 MHz system, whether Zigbee or other standard. The range is alway much more limited than the specifications suggest and the reliability is always marginal. Commercial systems like Innovonics are much better than any current "home" IoT system yet not much more expensive. They are not however packaged for IoT applications.
The Wi-Fi based systems like Ubiquiti are somewhat better, but still not quite reliable enough to be deployed with confidence.
My point is, the IoT industry made a good jump up in reliability when it moved beyond X-10 but now has stalled out, leaving fading hopes of a really solid solutions. This may result in flagging sales.
Does anyone have a different picture to report?
My findings relate only to Ubiquiti's mFi IoT power control system. I have no comments on their cameras (except for the generic negative of the closed system) and only solid results with their wireless links. Further, my experiments thus far a relatively small scale.