On Monday, 18 March 2019 14:19:32 UTC, DerbyBorn wrote:
We take for granted that we can find music on the Web - and Artist details
will be available about the track.

However, I find myself wondering who keyed in the information to make it
available. When was it done and what was the incentive - who owned it, etc.

That depends on many things, smaller band will do this sort of stuff themselves including art work and videos, and will write their won music and lyrics.

While some of the larger more 'popular' might well have people write and do everything for them.