Building and loading your own apps for tvOS isn’t hard but the instructions are always written for Xcode in its native environment (macos, formerly osx of xcode fame). You may have no problem setting up a vm for that, already have some device that runs macos natively or run into an infinite amount of roadblocks that you can’t surpass.

In the last case be careful what insane unofficial smarttube app you settle on.

You could also, and I wasn’t able to come up with a better way to put this because I’m not very smart so apologies if it seems like an attack, not watch youtube on the tv.