My mother told me about two, old, Christian widows that refused to have a TV or watch one when they came out because they thought the TV’s were watching THEM. My mom thought they were paranoid. As a kid, I knew they’d nailed it, and that was before Star Trek was released. Both my mother and father were HAMs so it was surprising. I imagine she updated her perspective eventually. Maybe by the time she got her extra class or got her captain’s license from the Merchant Marines. LOL.
I knew people who thought cable TV boxes did that. Seemed fringy to me, but at least the tech made sense. Before cable, you'd have needed a transmitter in televisions, because without them, they were just passive radio receivers. I'm really not sure how big-brother would have been able to spy on millions of TV transmitters if that were the case, but then again, maybe it's just something they'd have wanted to do only if they needed to by getting within range. Still, it seems unfathomable that such technology could have existed in so many appliances without being exposed by ordinary TV repairmen.