[deaddodo]

This is almost exclusively usually due to either producer credits or music licensing.

For the former, if it's really that big they'll just release it and keep a standard budget aside for if/when the unlocated people come out. The latter is what really blocks movies because it actively costs them money, so they need to be able to earn more than what it is costing them to release. This makes music-heavy/niche music films much more expensive for potential broadcasters/streamers.

[DropInIn]

As a minor musician, I have to say I find the entire legal model around music to be effing ridiculous and more harmful to the art and society than the benefit justifies

It all disproportionately benefits big names and corporations while small time creators and performers get screwed.

The moment recordings came into play it all got screwed up.

Before recordings every musician made their living exclusively from performances and every musician copied each other constantly.

We lost so much with the advent of recording and the associated development of copyrights etc.

The proof is in the numbers: management and corps take the lion's share of revenues within the industry, with the actual musicians and creatives getting a paltry pittance.