I will defer to you re: Modbus/TCP as it is outside my area of expertise. Even if these systems are "common," I would still claim that they are not the "norm" f

I will defer to you re: Modbus/TCP as it is outside my area of expertise. Even if these systems are "common," I would still claim that they are not the "norm" for the simple reason that I have been in buildings that were clearly "smart" buildings and ones that were clearly not, and the latter outnumber the former. However, even if it were the norm for commercial buildings, I was thinking far more generally and that may be the source of our disagreement. Automatic doors, for example, are the norm for major retail stores (as well as airports, et cetera), but they just don't exist in private homes. It would be expensive and serve no purpose, and that is how I feel about most "Internet of Things" devices [EDIT: and most "home automation" devices].