What makes you think the Apple TV isn't also spying on you? It almost certainly is collecting telemetry too. Whether that's more or less than LG I don't know, but my preference is a Linux box with Plasma Bigscreen.
At least you can replace it if that becomes a problem. Firmware built into the TV itself is something that you're stuck with.
What do you use when you switch between Netflix, AppleTV, etc? Some of those platforms won't even show you HD unless it's through HDCP compliant hardware and OS, which Linux isn't. That happened with the World Cup.