There will be many successful connected device startups. Many others will be started & funded for the wrong reason: because IoT is "hot" right now.
IoT is a particularly maddening buzzword because the name is mis-leading. There's not a separate internet for things, but rather these are just "things connected to the internet". Not as catchy, which I suppose is the point.
As an aside: I worry I may be turning into Andy Rooney :)