The most popular book of a period of time stretching from 2007-2015, the definer of an entire subgenre, four high budget blockbuster movies, an obsessive fanbase at the time that it was popular, and not even close to the amount of backlash that other series like twilight or divergent have gotten.

Seems underrated.

You might be psyching yourself up too much with the need to read “high quality” published fiction, and gravitating toward fanfiction as a result.

Look: I read a lot of litfic. I am literally an English teacher. And litfic is not always fun to read. There are published novels that offer all the raw pleasures of fanfiction, but have the polish that fanfiction doesn’t have. This is very common in the fantasy, romance, and thriller genres. I read a huge mix of “smart” and “fun” books, and I won’t tell you that the smart books have never been enjoyable, but they have also almost always been work.

Yeah, though I think it's still very bleak no matter what your religious views are. "The world is so hopeless that only heaven offers salvation" is probably the edgiest message in theological discourse.

I think that it's interesting how our readings of the book vary, since it is such an obtuse story, especially for science fiction.

I think what you're missing is how deeply Catholic the view of the world in the novel is is. Excuse me because it's been a while since I've read it, but there is salvation in the book. It's in the very subtle depictions of the Sainted immortal man who appears (implied to be Leibowitz) and in the idea of ascending beyond this world. The world itself, however, is deeply influenced by the Original Sin of mankind, and the pursuit of making the world a good place to live is ultimately hopeless. The monks do right by god but ultimately fail, and their only hope for reward is in heaven. Because the book does not confirm that heaven exists, it becomes a deeply depressing read for people who are not religious, and a story of endless striving and ultimate rapture for those who are. It's a strange and genius way to cause the reader to reflect on their own beliefs.

I think my reading is accurate because the questions of faith are brought up in the book itself in the arguments between the atheist and religious character in one of the generations (that's what I've taken to calling the different parts, lol). I would say the assertion of the book is simply: "This is what humanity's history is. Decide for yourself whether it is meaningless."

Unfortunately, the translation of the books leaves a lot to be desired. I don't know whether or not that makes them harder to read for an ESL reader, but I can confirm that the prose is not great. It becomes even harder to enjoy when a common criticism of the series is that the plot is difficult to understand due to a confusing chronology. (And that isn't fixed just by reading English better.)

This is my favorite Clarke novel, and it holds up remarkably well. With all the bad news about humans making critical mistakes with their world, I needed it.