They advanced together ajGoes, so yes, some of each.
The Germans who invented mp3 (and AAC too, not lot of people know that) had to wait about 20 years for certain technical improvements and market conditions, like more widespread broadband and mass market mp3 players , before their invention really gained momentum.
So even that "sudden" revolution took about 25 years in total, and against a lot of resistance.
Part of their story told in the book
How Music Got Free , which you have probably read. Well worth it if you haven't.