The benefits of technology and techniques don’t spread right across the whole population immediately—the primary benefit goes to the inventor and those near to them.
So, in the ancestral environment, if inventing a new kind of pointy rock to better kill dinosaurs gives you +1 fitness points, and lying around watching stone-age TV until your neighbour makes a pointy rock then stealing it gives you +2, then genes for inventing will spread until everyone has a 1⁄2 chance of having an inventor for a neighbour, at which point equilibrium is reached and both gene types will do equally well.
Warning: worthless evidence-free armchair evopsych speculation coming up:
The benefits of technology and techniques don’t spread right across the whole population immediately—the primary benefit goes to the inventor and those near to them.
So, in the ancestral environment, if inventing a new kind of pointy rock to better kill dinosaurs gives you +1 fitness points, and lying around watching stone-age TV until your neighbour makes a pointy rock then stealing it gives you +2, then genes for inventing will spread until everyone has a 1⁄2 chance of having an inventor for a neighbour, at which point equilibrium is reached and both gene types will do equally well.