The Catechism of the Catholic Church takes the view that the events in Genesis are historical events that are presented in representational language / speech, so that we can trust, for example, that there was original sin.
So much of this “fiction” stuff is superficial fluff, since we are looking for the personal and general meaning of scripture. To say that it is fiction is virtually irrelevant to a believer who is looking for what God is saying to them.
The historical critical exegetes (HCE) seem, more often than not, to want to draw attention to their own opinions and beliefs, than to the truths that we get from scripture. As the saying goes, keep your eyes on the ball.
The HCE’s that are the most malignant are those who maintain that not only is scripture not true, but that it couldn’t possibly be true. Therein, they betray the required scientific objectivity which they claim as their cornerstone of analysis.
The late Fr. Raymond Brown (like others of his disposition )dismisses the infancy narratives of the gospels by ***his personal opinion * ** [see his 101 Questions and Answers about the Bible].
An upheaval in astronomy that occurred in the last 25 years deals with the origin of Earth’s moon. The prevailing view was that it formed with the Earth. That idea has been replaced by the idea that a planetoid struck the Earth and the resulting debris formed the moon that we know and love. True science can turn itself on its ear so we might expect such in the area of biblical exegesis. Don’t be afraid to reject the latest bible commentary you run across.