I think several things are going on here.

1. I do believe the split is the product of our culture, of a scientific process being hypertrophied into an epistemological worldview thus 'literalising' the world into the true and the subjective, through postmodernity when the scientism of modernity that brought this about has been dropped by most people and we are left with absurd debates such as "I feel like a woman on the inside vs you're a man because of your body", or "a fetus is a life objectively" vs "it counts as a life based on my choice".

2. We also have forms of knowledge from science itself (e.g. evolution, archaeology etc) that cause us to actually have to ask questions about what kinds of text we are dealing with directly, so as you pointed out, Paul wrote to people who took the Torah as authoritative so was just not interested in arguing about creation or Eden as symbolic or literal and did not have to, no one would question his taking it symbolically because they accept it as true. The poet T. S. Eliot said about poetry that "the surface reading of a poem is like meat thrown to a guard dog by a burglar" in other words, the distraction that allows the real work to be done. This is in some sense true of just taking a text as 'literal', it allows a door into its meanings without you having to first deal with this question of is it true and then ok what kind of truth is it, is it literal, is it arbitrary and subjective, etc etc.

If you're really bored or that way inclined I did write an essay series on this:

https://medium.com/atlas-writes/the-meaning-crisis-and-language-bf7200daf682

https://medium.com/atlas-writes/the-meaning-crisis-and-language-ii-do-we-need-to-believe-myth-and-metaphor-in-order-to-6544c07f826d

https://medium.com/atlas-writes/the-meaning-crisis-and-language-iii-myth-faith-ethics-and-aesthetics-c25b2b626076