I thought that way for a long time too - but ultimately I think the limited/artificial soundstage with headphones has to hold them back a bit, in the realm of merely "very good" rather than "nearly perfect".
My headphone rig objectively sounds better than my speaker rig, but the speakers ultimately sound more natural, even if by objective measurements (e.g. frequency response) they're markedly inferior.
(Neither rig is super high end, not too far above the ~$1000 system at the end of the article, but they are all properly chosen and installed components.)