I think some parts of it are correct. It is definitely very interesting, but i dont think the metatron is rewriting the book of life, in my opinion there is no foreshadowing whatsoever to suggest this. Did this season feel strange? Yes, it did, but as someone said before, im getting bbc sherlock season 4 flashbacks :D do i trust neil gaiman that this has a purpose? Eeeh, i hope that it will, but once again i am wary of believing it is bad on purpose when s3 is not confirmed yet, in my opinion it is too much of a risk. I definitely think that the metatron is pulling the strings in some ways, either by "just" manipulating aziraphale, or possibly something bigger. The biggest Clue i believe to be muriel reading the crow road at the end. "This Bildungsroman is set in the fictional Argyll town of Gallanach, the real village of Lochgair, and in Glasgow, where the adult Prentice McHoan lives. Prentice's uncle Rory disappeared eight years previously while writing a book called The Crow Road. Prentice becomes obsessed with papers his uncle left behind and sets out to solve the mystery." This in my opinion is suggesting that muriel will find something in the bookshop(more specifically in aziraphale's journals) that will lead them to finding out what is going on.
I saw someone say that any of this still doesnt answer the question why and i wholeheartedly agree. Why is the metatron so keen on controlling aziraphale? Why him? Why is aziraphale special in this way? And because i have no idea how to figure any of this out, i sincerely hope we get season 3 to find out.