I imagine the artist approved a (stereo) mix they heard on decent studio monitors and maybe stereo headphones too. I’m not sure how they’d feel about someone else then creating an atmos/spacial audio version without their involvement. Mixing is integral to the artistic part of making recorded music.

I’d be interested to know whether the tracks appearing on Apple Music are being created from the original tracks/stems (i.e. properly remixed), or whether an algorithm is being applied to the same stereo mixdown that would have created a standard (stereo) master.