For instance "sound stage" is a vague term that can mean many things, but it is still useful. On different equipment (and even different volumes) the positioning of an instrument in my room can sound further to the side of a speaker or more forward. You can say its nonsense because you can't directly relate it to a frequency graph, but it is describing how the mind perceives the sound.
If you hear the MQA stuff it tends to really float around the room, I'm told there is some sort of phase shift due to non-linear filters. Using terms like it sounds like phase shift is meaningless, explaining how it impacts the sound you perceive is more useful to understanding what that sounds like. Q sound if I recall from a long time ago also played with time alignment stuff and had a similar sort of tripiness. Anyway terms like soundstage and positioning of instruments in the soundstage are not nonsense, in some sense they are talking more about the actual experience of the sound.