I have noticed that Christian apostates and anti-Christians in general, often focus their attacks on The Book of Job - above and beyond any other part of the Bible.
For example, when the mythologist Joseph Campbell was giving his most mockingly anti-Christian lectures, he would often provide a summary of Job which emphasized God's nastiness and highlighted an irrational and authoritarian message. CG Jung wrote a whole book about Job (which I fund incomprehensible). And Robert Frost wrote a glibly facetious 'Masque of Reason' which was a continuation of The Book of Job.
Yet - from the perspective of someone who is analyzing Christianity - it is surely tendentious to focus on Job of all the books in the Bible: because it is either the least-Christian or else the least-understandable section of the whole Bible.
For a start - Job is very obviously a fiction, a story, a fable, a myth - and it is not a history, an Annal, nor a piece of theology - the whole way it is written makes that very clear.
Furthermore Job is - in the Authorized Version - astonishingly beautiful as prose; although I personally find it vastly overlong as a narrative. But the sheer sensuous beauty tends to suggest that it was substantially an aesthetic work (like the Song of Solomon).
Thirdly, it is perhaps the least transparent, hardest to understand, most contradictory Book of the whole Bible. Job strikes me as a puzzle to which the key has been lost - it is as if we nowadays lack some link or fact which makes sense of the whole thing.
At any rate, for anti-Christians to 'pick on' The Book of Job is a bit of a giveaway - it is the dishonest rhetorical trick of picking on the least relevant, most ambiguous, and least central thread of an opponent's case, as a way of trying to discredit, rather than refute, their whole argument.
Note: That a person 'Job' really existed is irrelevant to the point I am making - just as the reality (or otherwise) of a Celtic 'warlord' King Arthur is irrelevant to the status of Malory's Le Morte d'Arthur as a fiction.