They both need positional audio information, so yes the games (or whatever media) need to supply this. You're not getting positional audio in DooM 2 from just left or right channels. You need the positional information.
As for Sonic being a platform-level, yes it is, but the games still need to use it. It really just offers something the developers don't have to go elsewhere for in terms of having a spatial audio client for use and for development cases. Up to the developers for inclusion and whatever.
In the meantime, does anyone have the Atmos app? I had a "special" version of it for unlimited use and it was neat to experience, but I eventually went back to Stereo audio with that as well. The novelty wore off and I preferred the easier listening in Stereo as opposed to much-higher variability in the spatial sense. Maybe I'll try it again soon.
