It's LLMs. You can tell from the phrasing ("no X just Y", "isn't A it's B", "pure ___"), and because all of the sections except Screenshots say basically the same thing. A competent person would not write it like this and an incompetent person would not be this meticulous about grammar and formatting.

I realize this sounds exactly like "I can tell from some of the pixels and from seeing quite a few shops in my time" but I really can tell.

Edit: Also you can see this was made with https://github.com/features/spark, but that's cheating, it's more fun to make accusations based on vague feelings about the writing tone.