Some parts of this the manga dragged on for too long, but it picks up at the end.
Nausicaa's actions at the end make sense, since the "master of the crypt" was planning to destroy humanity and replace everyone with a new race, as I understand it.
Still, the ending message confused me a little. Was she saying it's fine for humanity to die out? I suppose it's true that eventually everything has to end, including humanity, but that doesn't make it okay to do nothing about it. Is everyone really going to die once the forest has finished its job?
Honestly, I'm not totally into the message.
Still 9/10, but barely. What I liked most about the story for me was the "twist" at the end. How the manga started being all about how "nature is purifying the bad humans" but later it turns out that it was all by human design. At first, the manga seems to be going all in on "humans bad, nature good," but later, it turns out things are more complex.