[tremon]

I don't think so. Even a dumb TV can have an OS controlling the program and channel settings, or respond to commands from the remote. Set-top boxes generally aren't any smarter than a dumb TV, so you don't need it for that either.

What we call "smart" are simply TVs that have a general-purpose OS, indeed to run apps. That doesn't have anything to do with TV viewing, but with fragmentation of the delivery landscape: with the current appification, every video outlet considers your TV to be part of their "user experience" and wants to control and monetize your TV.