In my mind, De La Soul was the forebearer of all the experimentation that happened in the early 90's. Early rap music had such a machismo aspect to it that even the women were expected to "act hard". Anything that veered out of that lane was called 'soft'. Pioneers like Public Enemy would experiment and layer depth of sound to their songs, but it still had that hard edge (aside from the Flav songs).

De La Soul showed that you could lose that edge, incorporate hooks, absurdism, musical flourishes and other experimentation into rap and still be seen as cool.

That next wave of college kid rappers that followed them were pushing rap in all different kinds of directions. Fusing jazz, pop hooks into the sound. They were dubbed the Native Tongues.

So, by the mid-90's you had artists like Warren G, Biggy, Tupac incorporating huge hooks in their music and no one even batted an eye or viewed it as 'soft'.