I dont think it matters whether you read the book or not. The performances are just awkward and flat. If you watched the “behind the scenes” segment after the first episode, you can see one of the issues - Brie Larson and Lewis Pullman have, ironically, no chemistry. They are making lasagna with a chef friend and barely look at each other; there was no banter and little eye contact between them.
Regarding Larson, it seems like by having to play a serious character, with succinct and often blunt dialogue, she gave the character little depth in the first two episodes.