Given how long ago modern humans developed should we be more advanced?

'Development' isn't a straight line. Even the idea of 'progress' being this automatic always-forward-moving thing is problematic. Historiographically, it's fallacious and somewhat backwards-projecting.

You might as well ask why it took us so long to develop nuclear weapons, when we have been committing warfare for so long.

This. Real life isn't Civilization 2 where you have tech trees and each technology unlocks the one a level above it til you get to build a spaceship. It just doesn't work that way.
 
From around 9500 BC, the eight Neolithic founder crops – emmer wheat, einkorn wheat, hulled barley, peas, lentils, bitter vetch, chick peas, and flax – were cultivated in the Levant.
and the crop plants themselves had to be changed.... it took a long time with a lot of chance mutation to get them into the forms that we planted at the beginnings of civilization. It wasn't as if you could have gotten all the ideas about planting crops way back then and just started sowing fields...
 
Top