Is it just me or is it a huge letdown that the text is all AI-generated? Or at least, in the same kind of saccharine style? Are people not able to detect this?

Didn't seem AI-generated to me. Just the short, three-word-sentence pithy style that's become really popular these days that LLMs have learned to ape. But IMO it actually works well here, it reminds me of Peter Watts's very human style (cf. eg. https://www.rifters.com/crawl/?p=11546).