What should I make of the basically terrible reviews of "Light"? I am curious to read it to see what you are talking about, but 3.2/5 on Amazon usually amounts to "really quite terrible".
It is not a novel about a world with rigorously defined and cataloged physical law, and it's certainly not about a protagonist's moral crusade against evil.
It's a novel (in my personal estimation) about the breathtaking and magical pace of the advance of technology, and how it amplifies all the great and awful things that make us human.
Eh, I've found the correlation pretty hit-or-miss. William Gibson's The Difference Engine is currently sitting at 3.0/5 on Amazon, to pick one example...