It's commonly thought (and obvious) that Yud wrote the book about himself so I doubt it. It doesn't really fit the rationalist playbook either, they take themselves excessively seriously.
The character's author-insert aspects are self-parody.
He's too fragile and prone to overcompensation for that, nice try. Of course he's going to back track after getting mercilessly mocked for it and then claim it was just a joke.
The first few chapters have a song scene parodying ghostbusters and a joke about the protagonist biting a teacher in a tantrum as a young kid. There's plenty of elements of crackfic parody in it.
> a joke about the protagonist biting a teacher in a tantrum as a young kid.
wasn't that literally Yudkowsky, tho
Not disagreeing that Harry in the story is an author self-insert, just with that it's a fully self-serious non-parody one.
At the end Harry is basically a Messiah that can order the magical world to provide emergency medical aid to everyone in the whole world and turns Hermione into basically an angel; not really seeing the story itself saying he did anything wrong...
You're describing one of the unofficial fan-written fanfic sequels.