I think it's because LLMs write things down that normal people wouldn't - they go the extra mile, but the reader isn't interested in the extra mile.

Which is an interesting development. I think a lot of people have gotten impatient with long form, high density content thanks to years of rapid fire short bursts of internet - comments, tweets, shortened or clip-edited videos and podcasts (removing all the natural quiet points, especially at the end of sentences so you get theseChopped sentences wherePeople talk likeThis so that youDon't hear any naturalBreaks in aSentence).

Having an LLM now have the relative superpower of reading everything with the same amount of detail and attention, and write something in response to it + filling in the blanks is a bit of a shock.