apple tv, youtube app

What model of Apple TV do you have? click here ➜ Identify your Apple TV model - Apple Support

Google stopped supporting 3rd generation Apple TVs and earlier for Youtube, there is no way to get the Youtube channel on those models anymore.

https://9to5mac.com/2021/03/04/youtube-no-longer-works-on-third-gen-apple-tv-here-are-your-options/

Personally, I would do a "Restart" or a factory settings "Reset".

Since there is very little data actually stored on your AppleTV, outside of downloaded media (ALL of which is downloadable again), in relation to an iPhone, iPad or Mac, this is a very safe and relatively quick fix.

You may want to spend some extra time doing searches for the App Store. I'm not entirely sure that that app can be removed from AppleTV.

Hope this helps!