Do you mean early human development biologically, or early human development overall (including culturally)? Because if the latter, humans using fire to cook meat was probably significantly less important than humans using fire for heat and light.

I know Greek mythology is very centered on the idea of fire being a defining things that made man civilizable. From Prometheus to the sacredness around keeping hearths lit.

Curious how many other mythos carry on those ideas tbh

I think the answer is complicated. Homo erectus, the first homo species thought to use fire and our direct ancestors were as close to obligate carnivores as there is in the homo genus, but they focused on big animals with a lot of fat like hippos and elephants. They likely did not cook that fat, because it would store just fine without doing so.