Why YSK: I saw a post on r/mildlyinfuriating about a person being angry about ads on their $2500 TV. Well, on any Android/Google TV you can install Projectivy launcher and completely do away with all of that, for free. There's others but I've found that one to be the easiest to install.
It works exactly like changing your launcher on an android phone. I haven't seen an ad on my TVs in years. No pihole, or DNS blocking, necessary.
Edit: To help with confusion, Projectivy (Or FLauncher, ATV, or any other launcher) is an app on the Android TV app store, you install it like you would any other app. Follow the on screen instructions and set the permissions it tells you to. And you're done. It should act as your home screen instead of the default, ad filled mess that's usually there. Projectivy is an open source, free app. I'm not affiliated with it in any way, I just enjoy the app, but there are many others to choose from.