Apple TV doesn't play some youtube movies I put this Samsara movie into my youtube favourites.

There are two unexpected issues here.  


If I try to play that movie either from iPad or iPhone and display it to my Apple TV my Apple TV said that it can't play this movie.  
The other strange issue is that the above movie isn't shown amongst the favorites on my Apple TV. However the youtube web interface clearly shows that it is my favorite.


This version of Baraka which is not Full HD can be played, but still doesn't show amongst my favourites despite the fact that it is there on the web UI:

Any explanation?
The reason your favourites do not appear in the listing on the Apple TV is that the owner of the video has not allowed it to be viewed on a mobile device (which the youtube considers the apple TV to be). The Apple TV recognises this and removes it from the list so you do not try and play an unplayable video.

The owner of the video (or more probably the copyright owner of the soundtrack) can decide whether to allow mobile devices and Apple TV's to display videos.