The trick is to never give your TV access to the internet and to pair it with an Apple TV. If you buy a TV and it won't even boot or work without an internet connection - return it and get a different one.
Do Apple TVs not display ads? I have Google TV devices, in part because I can install what er I want on them, including 3rd part launchers that don't have ads.
Been a user for the last 7-8 years and I love the UX.