And thus a crude stone age weapon is exactly the same as a carefully crafted steel weapon. By hearing those description I, and probably most other people, expect the steel weapon to be way better than the stone one and having them performing exactly the same is in my eyes, lame.
This is exactly why you don't let the players see your DM notes. If you keep things "under the hood" then you get the "cool" from the description and lose the "lame" from inconsistent mechanics.
I'd be more displeased if, as a player, I went up against a fearsome primitive tribe, and they were all using refined steel weapons.