XDA contributors have noticed that the latest update to the Android TV OS has resulted in the appearance of "sponsored content" on the launcher visible from several kinds of device. They include the Sony Bravia X900F, the Mi Box 3 and NVIDIA's Shield TV. At present, this can be circumvented by uninstalling the updates from a specific app.
https://www.notebookcheck.net/Android-TV-has-ads-in-its-launcher-now.415895.0.html
Baked-in ads on a high end TV? Unacceptable. At least I don't plan on ever using a TV OS anyway.