As Google had announced to YouTube users with a 3rd generation Apple TV, the application to view the content of this platform on this device is no longer available, so the only solution is currently to do AirPlay from an iPhone, iPad or iPod touch.
Removing this app does not affect devices that have access to the app store of Apple TV, only to the model that offered the application natively, an application that Google has stopped updating, a logical step since this model arrived on the market in 2012, 9 years ago and for 5 years it has stopped being sold ( 2016).
YouTube not the first application which is no longer available on the third generation of Apple TV. Last year, HBO also withdrew its application and shortly afterwards also the application of Major League Baseball (MLB).
If you are still using this device and you are thinking that it is time to renew, depending on how you use it, I would advise you you will wait a few months, since some rumors suggest that Apple is working on a new model, since the last one it launched on the market, the Apple TV 4K, has not been renewed for 4 years. The new Apple TV should incorporate a faster processor and more space storage plus a new control knob.
Is Apple TV worth it?
To this day, Apple TV does not offer us any function that we cannot find in the most modern TV models from Samsung or LG, models that also offer support for AirPlay 2, they also integrate the application to access both Apple TV + and the content available in the iTunes Store.