Xbox Series S [XBSS] [Release November 10 2020]

No, they obviously know about the flag but it reads very much like they wanted to write code that worked fine on One S and scaled seamlessly on Series S. Depending upon how an individual coder or team feel about it, it can be preferable to have one slightly more complex codebase to do this, rather than forking the One S codebase for Series S - for the reasons I said above.