Proposal: Internet of Things
There is an existing proposal for an Embedded Systems site that is already in the commitment phase right now. And if you look at the top questions on that proposal, the scope seems to cover working with embedded Linux, microcontrollers, different physical network interfaces, and so on.
IoT in principle will certainly have a lot of cross-over with embedded systems questions, hardware questions and programming questions. So what would make questions more appropriate for an Internet of Things site vs other site options like:
Specifically: What questions can you ask here that would be on-topic in "Internet of Things" but be either off-topic on other sites or need a more dedicated/specific user base & skill set than the other sites can provide?
Would the scope be specifically for IoT frameworks? In which case it might be too narrow to have a specific site (there is an IoT tag on SO) and you might be more likely to get good answers to specific questions in the existing strong/established sites.
(Note: See this other proposal Embedded Programming and Design that failed during beta due to having not enough activity)