How the tribe of Benjamin after the concubine incident went from being a wiped out people, to producing Saul as a warlord and unifying all Israel? It seems almost as if the davidic scribe of the Tannakh is trying to slander Benjamin/Saul by intentionally saying benjamites were homosexuals and rapists in the book of judges. I understand from a literary point of view, Saul being propped up by Samuel, but politically and militarily Saul would need his tribe and his soldiers for everything, and neither the unification or the war against philistines wouldn't be led by the warlord of a decimated tribe.
Rashi (to Judges 17:1) notes that the final two stories of the Book of Judges actually took place chronologically at the beginning of the Book. He notes that the Idol of Micah was said to be around the entire span of the Tabernacle at Shiloh (Judges 18:31), and likewise the concubine at Gibeah, the story which you reference, occurred before Jerusalem was conquered (Judges 19:12). So the Benjaminites had close to 400 years to recoup their losses, as follows:
The Temple was completed 480 years after the Exodus (I Kings 6:1). Subtracting out the 40 years in the desert, it comes out that the Tabernacle was in the land of Israel for 440 years. Since Solomon was in his fourth year at the construction of the Temple, and David had previously ruled for 40 years, following 2 years of Saul’s rule, it comes out that the Jews were in Israel for 392 years before Saul’s rule, including the period during which the land was conquered and divided.