The real lesson and historical factor here was the eclipse of the here to fore arm of decsion, the branch upon which battles had been fought and decided byall national armies ( aside from the Parthians), the infantry.
The change to mounted forces as the arm of decision ala the Cataphract, Knights etc. was an event that changed the course of how armies were built and how they fought for centuries there after.
That 'verdict' of Adrianople was turned around at the battle of Crecy. Though there were other examples of infantry defeating armies based on cavalry forces, the battle of Tours for instance in the early 700’s, infantry really became predominant again after Crecy, and until this day.