I doubt it. The business overhead of distributing payment this way is enormous. Right now, Spotify just runs a report that takes some top level numbers, splits them out by copyright owner and divides a single pool of money. This means they manage only as many pools of money as they have copyright owners.
If they start doing it the way OP suggests, they DRAMATICALLY increase the number of pools of money they manage (and thus, would need to audit). They'd now be managing (number of copyright owners) * (number of subscribers) pools of money, which is a lot more. Additionally, they likely have some errors in their data, and the impact of an error in this scheme is huge.
tldr: It's too much work for too little money. Improved technology will not change anything because it's a finance process problem, and finance processes have to be regularly audited. The more complicated it is, the more expensive it is to audit.