If you are only familiar with Swing Dancing - you will have a tendency to hear all music as Swing music. A good Swing dancer can dance Swing to any kind of music that plays. That does NOT make the music “Swing Music.” All social dance music, with the exception of Waltz, has the same number of beats per measure. It is the OTHER properties in the music that define the dance. Those subtle DIFFERENCES allow us to identify the dance that should accompany specific music. If we do not know about a particular dance, that dance does not exist for us. Our computer (brain) will fit whatever music it hears, to the closest form that fits our personal frame of reference. Our frame of reference is only as good as our education. Educational observations of various dance forms, gives us the confidence that comes with any form of education.
MUSIC is crucial. A really good dancer will adapt to whatever music is being played. However, if the music being played is NOT the music of the dance being danced, the dance will take on the character of the music being played. To some degree the dance will LOSE some of the “essence” and characteristics of the dance being presented.
Starting in the late 1990s, newer swing dancers seemed to assume that all music being played at a swing event - was Swing music. Anyone who has been around for a while knows that swing dancers will dance swing to any 4/4 time music that is played.
Another thought, my own, as best I can determine, is that "West Coast Swing" seems to have become a brand name.