I honestly think the styling is the main reason it feels AI.

because the sentences are too short, they're a style I sort of writes at times. Just sort of. LLMs tends to output longer sentences, rather than the two-three words. Then dot. That's a rare one for LLM

However it's not an anti AI site, so they might have vibe styled it and probably had a LLM help with some of the wording. However I think a human did vet and rewrite parts of it.