Air isn’t some ephemeral thing that simply appears between your speakers. “Air” isn’t air! That sense of openness and space is precisely the presence of harmonics from notes in the midrange and treble. Air is largely created from harmonics and resonances. Air is important musical content. It helps define subtlety, nuance, and artistic skill.
The other component of air is the natural fade-out of a piano note or a bell ringing into silence. Listen to the Rob Mullins Band album “One Night in Houston”, Audioquest AQ1020, an all-analog recording direct to 2-track. This album has vast quantities of “air”.