You could certainly be forgiven for thinking that its not possible for headphones to give the impression of imaging and depth ( soundstage ) BUT your ears and brain work rather well at doing just that !( Its probably a similar mechanism to your pair of eyes giving depth perception ) with some good in ear monitors ( properly positioned ) and a good headphone amp it can be quite startling , with traditional headphones the effect is not unlike well positioned stereo speakers . I have found that many Spatial Audio recordings can be pretty good through a pair of speakers but sound downright odd through headphones , again its one of those weird auditory phenomena .
Where speakers do have the edge is in body resonances - ie getting your chest cavity to resonate at ultra low frequencies - now that would require one heck of a pair of Headphones
Its a fascinating subject