Hi OP - I have a HT set up and that shares the space and some equipment with my 2 channel space. Atmos via Apple or another streaming service isn’t designed to provide a benefit into a 2 channel set up. As a previous poster mentions, it does make sense via headphone potentially but not in a 2 channel set up.
I would only look into Atmos for music if you wanted a HT set up with a speaker configuration and equipment that supports Atmos.
For music listening I prefer my 2 channel set up vs Atmos via my Anthem MRX-1140 HT receiver driving my Atmos speakers. I find Atmos via my HT set up to be a novelty, some songs can be really immersive but from a sound quality standpoint, 2 channel is far better, your mileage may vary.
Again, to recap - unless you want a HT Atmos set up, receiver / speakers there isn’t a benefit, point to adding a HT Receiver to decode Atmos. Without the extra speakers, you won’t hear the intended differences from stereo recordings.