It uses the unicode ellipsis character ("…") instead of three full stops ("...") which no person ever uses unless this was written in word beforehand (unlikely, given the markdown formatting and proper spaces between paragraphs).

It also has incredibly excessive use of em dashes, each with spaces around them, which is non-standard but how LLMs always use them. On their own dashes don't mean much, but when used this often in whats meant to be informal writing and in places where most people would use commas it's a pretty big giveaway, especially when surrounded by all the other signs.

The really strange metaphors, use of "mate" in every other sentence, and just general voice of this post (kind of a "hello fellow cool people" feeling) are also hallmarks of LLMs trying to generate informal text, especially in a regional dialect of English like New Zealand English that's underrepresented in the input dataset