It reads okay to me too, yet Pangram says it's mixed - the "What a private key actually is" section is AI, so is 'Why "it cannot be contained"' and some others.

I think it's a hybrid text. The section about how elliptic curve keys work is particularly aggravating. Unfortunately it's also the only section that gave me new information.

It has parts that are human written and parts that are generated. I couldn't tell at first, but now seeing it in Pangram, it's kind of clear.