It's more about our audio team licensing blocks of music from labels (then picking out tracks from that block) rather than choosing individual songs (unless it's a mission moment that we need something special for.) We plan on doing a future stream about how it all works.
It's a very complicated answer to a seemingly simple question. Everything you need to know was talked about on our stream for it:
youtube.com/watch?v=YYvAO6yO…
Asking the vitally important questions, we see. We're going to go with either a time paradox, or a simulation within a simulation leading into sr4. That work for you?