While you should never do it in public, those phones with the virtual 3d sound field speakers are starting to get pretty decent to listen to music on. Still, never listen at higher volumes, cuz that breaks it. But it’s pretty awesome for any volume level where it can manage the right level of base for the song.
Specifically what it’s doing is making it so each ear only hears the part that is meant for it, and doesn’t get the bleed over from the other speaker. Virtual stereo isolation, the Switch 2 also does it in standalone mode. But yeah, of course, that only works for the primary user, anyone in the wrong physical location relative to the speakers won’t get the effect. And actually it’ll just sound weird to them.
Could sort of be described that way. But they basically just shape the sound in a way that your ear hears it with the specific acoustic distortion that normally cues your brain that the sound came from behind you. Or wherever.
So in the sense that a hologram is using different properties of shaping light to trick your eyes that something looks different than it really does, then yeah, audio hologram sort of fits. And similarly, it only works if your ears are exactly where they expect them to be, just like a hologram with your eyes.