YouTube TV 4K not working on my Apple TV 4K

The Apple TV 4K started supporting the VP9 codec over a year ago when tvOS 14 was released.

https://www.idropnews.com/news/youtube-has-begun-gradually-rolling-out-4k-support-for-the-apple-tv/144434/

Pay attention to the limits and restrictions part of the article, like no HDR support yet from YouTube.

Sadly, it’s not all 4K sunshine and roses just yet, as YouTube appears to have still a few limitations on what videos will play in 4K on the Apple TV. Right off the bat, it seems that only 30fps is supported right now in 4K. If you attempt to play a 50fps or 60fps 4K video, YouTube won’t just try and lower the frame rate — it will actually drop it down to 1440p resolution.

Comment💬HDR is also not supported right now. Although you’ll still be able to watch 4K HDR videos in full 2160p resolution, they’ll be rendered in 4K SDR instead.

Hi RobbieBobbie1,

Thanks for coming to Apple Support Communities for help today with YouTube 4K on your Apple TV 4K.

This should be available for you. Do you receive other 4K content? Is your HDMI cable a 2.0 cable?

If 4K works elsewhere, we'd suggest contacting YouTube support to find out how to enable it for their app: How to contact an app developer.

Have a fantastic day!

YouTube Tv has horrible customer support. I have tried to sign up for 4K on YouTube tv as I select option but it does nothing.