The judge/law will say it comes down to intent.
Here's my take from an audio DSP viewpoint.
A composer listens to 10,000 hours of music. One day she writes an
original piece based on the annealed parameters (temporal, spectral,
intensity, pitch, sequence...) of a million artists. However it sounds
like another specific artist who sues.
It is not a cover, a remix, homage, or even forged in the
genre... it's just accidentally a bit too like it. (compare: Banana
Splits vs. Bob Marley - and - Huey Lewis vs. Ray Parker Jr. - which
completely misses the real impact of "Pop Muzik" by M)
The question is, was she exposed to influencing materials incorporated
without intent or was it plagiarism (intent to reproduce a derivative
etc) ?
By contrast I can take a piece of music, break it down by analysis
into melodies, chords, timings, and use FFT to extract the precise
spectrums of instruments, feed those to a resynthesis engine that
finds new synthesiser parameters to create an exact sound-alike and
then deliberately recreate a piece "In the near style of artist X".
With a little musical processing I can change the key, inversions,
re-template the rhythm to a new swing... always pushing the derived
piece into new territory until eventually it's barely recognisable.
Nonetheless, in the second case I have clearly intended to steal
someone's idea and "make it my own" by automatable transformation.
In the former case it seems to be a "genuine labour". (whatever that
means in 2023)
The genuine artist intends to make something through intellectual
labour.
Maybe that's the real question. I mean, about "labour". If the cost of
the labour tends to zero, does it really matter?