Microsoft responded with the following in an email:

"A blog post was mistakenly published by a local Xbox team that included inaccurate information regarding exclusivity of Dolby Atmos and Dolby Vision on Xbox Series X|S. There is no exclusivity agreement of either tech on Xbox. We are proud to partner with Dolby to offer Dolby Atmos and Dolby Vision to gamers on Xbox and will have more to share about the general availability of Dolby Vision on Xbox Series X|S soon."