old news - this was announced almost a year ago.
https://9to5google.com/2021/06/28/youtube-tv-surround-sound-dolby/
@UserOfStreamers The article was updated. Entirely different articles. Your article is about YouTube TV adding 5.1. They have already added it on certain devices. The new article is an update about support for Roku coming
Yes, different articles, and old news - YTTV 5.1 (including for Roku) was announced almost a year ago.
They have repeatedly issued "coming soon after testing" announcements - old news.