The author's fixes based on the slop are good, because he knows the issue is slop and therefore can improve and fix the sloppiness.

Ignoring AI for a moment: I don't expect anyone to be able to write a design-doc from my own random notes about a problem. They are semi-formed, disconnected ideas that need a lot of refinement. I know that and I have plans around them and know much more context, but if some random person were to take them the outcome would be very bad, or at least require a lot more effort.

A random person has very little chance of being successful with that.

This issue is very similar, only with some AI tools intermediating the notes.