Depends on how you use them, I think. Magic boxes that are tied into the cloud and just give you an app to control your lights, dumb. Setting up a system that automates your home electrical appliances in a thoughtful manner can actually deliver savings and maybe even improve your life. Even as someone getting into smart home stuff, though, mainly what I'm seeing is the ability to save power by having some kind of intelligent control over your devices. Everything else is flashing lights and surveillance.

Problem is, your average user isn't going to be setting up a LAN-only, zigbee-to-homeassistant automation. They need the magic box type of interface. So as a mass market thing it seems kind of doomed.