Yeah, Television as a “do-all” device likely will never work as folks have found that the living room is not the most comfortable place for all they want to do. I would imagine there’s some folks that remember their WebTV fondly and would like an updated “that”, but it’s just nostalgia.
The only people I know, family, that had one were an aunt and uncle. They 'loved' it, but were the least involved family members with social media and email. I think a large part of that was the clunky interface. Maybe a 'WebTV' like device would work better with today's much higher resolution tvs, but I still think it's such a niche product it wouldn't sell well at all. I have an Apple 'short' keyboard sitting in front of the tv in the 'great' room, and have never actually used it. I thought it would be 'useful', but it's just drawing dust. If they supported Safari on the ATV, would I use it more, or at all? Doubtful. I use an iPad or my MBP on my lap if I need it, something like the Weather Channel, or CNN on in the background.
A webTV like device would likely only appeal to the people already in the 'digital dessert', or really don't use it at all very much. It would seem to be more usable, but its not. If it was, it would probably still exist.