Copyright treats music, lyrics, and recording as separate entities. The recording of a song is a derivative work of music and lyrics. I'd strongly favor shortening the copyright on audio recordings, while keeping the copyright for music and lyrics strictly with the composer and writer, respectively, for a longer term.
The same could happen for video recordings and their screenplays.
I think maybe the "works for hire" regime needs to be changed such that employees own the copyright to their own contribution to a work, and the employer just gets an automatic perpetual license only to works created while on the job, exclusive only as long as the employee remains employed, and the final aggregated commercial product is a derivative work from many sources. So if you can reassemble the same team of actual humans as the original, you can re-do the work of putting their contributions together, and acquire a new copyright on a new aggregate that could be nearly identical to the older aggregate.
So you only hold a monopoly on a movie as long as the majority of key contributors in that long credits scroll at the end continues to work for you. If you fire too many people after production wraps up, particularly the script writers and scene planners and digital modelers, they could get together, compare notes, and do a shot-for-shot remake at a fraction of the budget, because their part of the work has already been done, and you lost exclusivity when you fired them.
That would surely invoke a new form of Hollywood Accounting, but at least it would encourage creators to create works with some durance in preference to consume-once ephemera. And you wouldn't end up with great artists in poverty even as their works make their current owners heaps of money.
It is still important work to turn an artwork into a viable commercial product, and to assemble and manage teams of artists to great something together greater than what could be produced individually, but that added value should not make the middleman the sole gatekeeper for the source works, forever.