Chimpanzees are omnivores and as a species have only been around for ≈5 million years. 

Humans likely evolved completely separately and during our own evolution we became adapted to being hyper-efficient / intelligent predators that subsist off meat. Here is a good presentation that outlines some objective evidence that indicates we are very likely adapted to subsist from meat: https://youtu.be/C-WUb3mJEso?si=MM1D428eNqRps-Ld

There are different classes of carnivores - scavengers and predators. The latter eats dead things after they’re dead. The former kills and eats immediately. That distinction  would explain why vultures show up to feed on carrion but why humans and many apex predators are repulsed by rotting flesh.