Rigid rhyme scheme versus flexible rhyme scheme ... The ChatGPT text has a pretty consistent and neat rhyme scheme, which ends up sounding rather mechanical, even forced.
This is in contrast to the Nick Cave text, where there is a rhyme scheme which is not emphasised, and even wobbles and varies at times. This inconsistency suggests that 'neat' rhymes were given less priority than the need to express emotions appropriately, even if this disrupts the 'correct' pattern.
(And incidentally, the Nick Cave text implies and responds to the music which actually accompanies it, with variations and developments - the ChatGPT text suggests a simple, repetitive pattern of music... even if this was ever a factor in the process of composing the text.)