Whether PC, Mac, smartphone, or tiny Linux kernel in a light bulb, they are all computers. It’s just that a large number of them have NO security. IoT Security: Deja Vu Or Part 2?
Researchers we able to hack into the Philips Hue ZigBee Light Link Touch System from an aerial drone more than a thousand feet away from the light source to remotely control the Hue lights and cause them to blink S-O-S in Morse code. Fundamentally they injected one lightbulb with a worm, and that bulb infected its neighbors, and so on, and so on—infecting an entire building in a matter of minutes.
I’m sure there is some reason you want your light bulbs controlled via some wireless protocol. I doubt you want them to be under the control of some random hacker.
Aside from losing control of your light bulbs, they can be used in DDoS attacks. Not good.
Web cams (including baby monitors) that let strangers spy on you. Hacks into your personal network (where you might keep things like banking and tax data). Just because something is “neat” doesn’t mean that you have to buy it.