Since there doesn't exist a good panel without Smart TV capabilities, what I do is just don't give them access to the network. Everything runs through an Android Box connected to an HDMI or a PS4 when I want to use Netflix (I never managed to make it work on the Android box)
Eventually they'll just ship with some sort of connectivity out of the box.
If consumers are 'lucky' it will surface as something they can use. But the bare minimum of a persistent connection to load you ads and track your usage seems inevitable.