Why is it great? First off, the rhythm of the sentence makes me swoon.
I keep reading it aloud, to hear how it swirls and swirls like dancers on a ballroom floor before coming to a rest, softly, on the words champagne and stars. But it also captures Gatsby’s world: People are drawn to him like moths to a bright light, but his gardens are tinged with sadness and filled with whispers, for it is the champagne and extravagance that bring them, not love.