My understanding is it sort of relates to a simulated acoustical physical space the music is intended to seem as if it is reverberating throughout
Is it correlated with the intimacy or closeness of the music, what else does it evoke? What is its relationship with artificiality and nature respectively?
What is its evolutionary purpose in terms of why we can parse and interpret it?
It’s simulating an echo. I don’t really think it’s deeper than that. It’s use could be to envoke the idea of a large space, or just because it sounds cool.