The 'Fad Phase' has gone. Now there is the quiet background development phase. Things are still happening, but you won't hear about anything until such time as something is released. And then that release will be heralded as "New Object X' rather than 'just one of many IoT objects'.
In my opinion, most of these objects will have embedded intelligence based upon one of the many SBCs (arduino, raspberry pi, risc-v, etc) in the short-term until dedicated ICs can be manufactured to suit each particular object.
It'll be the old 'economies of scale' factor: when an object becomes a best-seller, it'll then become economic to use a dedicated IC to make a more compact, energy-efficient 'Thing'.
