I may be counted among the nuts who are afraid of a Skynet-type of control. I do not envision it in a Terminator-end-of-the-world kind of disaster, but I don't see why interconnectivity may not degenerate into centralization, and I think we've seen the results of that in politics and economics.
The popular saying warns us against "putting all our eggs in one basket". If the basket goes down, all the eggs break; if the basket is stolen, so are all the eggs.
Besides, it will be a while and it will take a lot of heart (not bots) before more than 5% of the population have any eggs to put in that IoT basket.