[Grishnakh]

Why would anyone want this?

If you just want cheap service, you can already get that with a full-fledged smartphone with data. I pay less than $20/month with Ting, and I'm sure you can get similar deals with other MVNOs. You can't constantly stream YouTube videos all month long for that price though; you get that kind of bill by not using your phone that much, and doing a lot of your talking over WiFi using VoIP apps.

And you can get "burner" flip-phones for next to nothing anyway which will do exactly what you want here. If people really wanted stripped-down phones that much, those flip-phones would be extremely popular, but they're just not. There's no "revolution" to be had here.