FWIW, the best source of GPT-3 poetry, if you want to see what it can do beyond the cursory discussion in OP, remains my own https://www.gwern.net/GPT-3#poetry page. (Pointing out, among other things, that GPT-3 can't rhyme and so Andrew Brown's sample is a bit misleading about capabilities.) I'm surprised it's neither mentioned nor linked, since there is not that much GPT-3 poetry out there...
OP argues that GPT-3's poems 'fall dead' and never become 'a memorable unity'. I will just say that for me, a number of GPT-3's poems like "Uber-Poem" (https://www.gwern.net/GPT-3#uber-poem) or "The Universe Is A Glitch" (https://www.gwern.net/GPT-3#the-universe-is-a-glitch) struck me as a good deal more lively and memorable than the vast majority of the poems I puzzle through reading the New Yorker or Paris Review.
OP argues that GPT-3's poems 'fall dead' and never become 'a memorable unity'. I will just say that for me, a number of GPT-3's poems like "Uber-Poem" (https://www.gwern.net/GPT-3#uber-poem) or "The Universe Is A Glitch" (https://www.gwern.net/GPT-3#the-universe-is-a-glitch) struck me as a good deal more lively and memorable than the vast majority of the poems I puzzle through reading the New Yorker or Paris Review.