As a musician, I think what would happen is the companies that abuse copyright now would keep abusing musicians, except now they can just take any song they like without compensating the person who made it.
The melody copyright is where things get really hazy. It's hard to determine when a melody infringes on another melody. What if the notes are the same, but the timing is different? What if the notes aren't exactly the same, but are pretty similar? What if the main melodic ideas are really common in a given genre or style? How do you determine if there was actual copying, or if two musicians just came up with the same idea independently? What if the melody just isn't an important part of the style of a given work? What if the melody is almost the same, but used in a completely different musical context?
There isn't an objective set of criteria that can determine if a melody infringes on another melody, without being too narrow or too broad. And since there's no good criteria, the only way to litigate this is to have better lawyers then the other guy, which rarely works out well for independent artists.
[1] At least, uncontroversial at a high level. The details get messy really quickly.
https://www.buzzfeed.com/reggieugwu/what-the-law-says-about-...
> Copyrighted elements of a musical composition can include melody, chord progression, rhythm, and lyrics — anything that reflects a "minimal spark" of creativity and originality.
https://ask.audio/articles/5-common-beliefs-about-song-copyr...
> Song Titles and Chord Progressions are not copyright protected
> This is true.
[snip]
> Ditto for chord progressions. There must be hundreds of songs that were hits in the ’50s and early ’60s that followed the familiar “ice cream changes” progression of I-vi-IV-V7. Thin “In The Still Of The Night” (another song that shares its title with others), “Donna”, “Silhouettes”, “This Boy” just for starters. Also the chords from the “Pachelbel Canon in D” have been used numerous times. Think “A Whiter Shade Of Pale.”
Does lack of enforcement make something legal?
https://moviecultists.com/can-chord-progressions-be-copyrigh...
> "If a single chord progression were elaborate enough and unconventional enough, it could be protected."
How many possible chord progressions are there?
