A lot of critical book reviews seem to completely miss the point of the book. When the reviewer is an expert, they might say that "there's nothing insightful here" of a book about their field aimed at the public. Or if the reviewer is a theorist, they might say "this advice isn't generalizable" when the book is aimed at practitioners, who learn from idiosyncratic case studies. Or when the reviewer is me, they might say "this is 100 pages of adventure and 300 pages of romance" and quit the series in frustration.

In each of these cases, the reviewer went in with some expectations for how the book should be and when it didn't match those expectations they became upset. This happens quite often. However, that does not mean the book is bad.

In general, you should discount a lot of book reviews. Reviewers will often have different purposes and expectations compared to yours, so the features they attend to in a book review may be totally different from what you attend to. You can sort of tell this by the content of a review. If a reviewer talks about how a book uses theory X instead of theory Y but doesn't mention how that undermines the book's central thesis, then they're probably an expert in the field. If a reviewer talks about whether a framework in the book is true instead of whether it's useful, they're probably not a practitioner. If the reviewer talks about how little adventure or action there is, then they're probably not a romance fan. A member of the public, a practitioner in the field, or a romantasy fan, you should discount these book reviews. 

In general, I wish reviewers made it clear what their motivation for reading a book was. Perhaps a "context" or "motivation" disclaimer at the top, like an epistemic status? It would help potential book readers figure out if the reviewer's criticism is relevant to them.