I’ve not read the book, but I know the basic outline and read the TV Tropes page and listened to videos talking about the book.

I think its a brilliant and horrifying piece of literature. It saddens me how easily the invading aliens are able to split humanity apart into various species. And while I slightly agree with some people who view the book as an optimistic story because of the ending, I still think that’s a very charitable way of viewing it, rather than a story of humanity being genocided and treated lower than dirt before finally taking revenge, and things wouldn’t be the same as they ever were.