I think the challenge is that the majority of today's creative talent resides in those with humble budgets and TMB model is still a bit behind the times in today's video production reality. When Avid has gone to subscriptions and you have sites like Art-list.io exploding in such a short time, it's going to take more than flashy videos to convince small to medium filmmakers to keep using this licensing method.
My 2 pesos
Music licensing seems like an unending web of legal rights clauses that were created under an antiquated system 100 years ago. Tin Pan Alley all the way. :(
Great to see some creative forward-thinking people like Art-list.io, and to some extent others, bringing music and film together in a mutually beneficial way.