The ending itself was a bit underwhelming. The whole book felt like it's just writing out everything that you probably already guessed was going on in this world. It's still a 4/5 because the whole series and this book wasn't bad, I just expected much more of it, especially because of the hype around it.
Speaking of the series, I don't get why people love it so much. It's just another sci-fi series. The characters weren't outstanding, the story and world-building is okay-ish. It was a fun read, don't get me wrong, but it's not very rememberable. I feel like I could have skipped half the book and it wouldn't even have made any difference.
I would not recommend this book, not because it's bad, but because it's not special or exciting in a way that it stands out from other sci-fi books.