The earth has had massive temp fluctuations throughout its history .You are referring to the pre Cambrian period around 3000 million years ago when the earth was cooling down…and before the climate as we know existed.
That’s a period 2999.7 million years before man arrived
Im not sure your argument is working terribly well for you
I guess it was all that industrialisation 12,000 years ago that brought an end to the last ice age