It’s only recently been proven untrue… IIRC… because it apparently turns out crude oil is actually the poop of a particular ancient microbe that is still around and that’s partially (along with Oil Fracking) why we still have fossil fuels and why a far future non-human civilization will have plenty of fossil fuels to work with.

You’re right, though, we have 5x more fossil fuels than have been burnt since the beginning of the industrial revolution. If we DO use the rest, the climate would be so unrecoverable that 99% of multicellular life will die, but even the most corrupt oil executive would be dead years before the last animal because most - especially the wealthiest - humans need agriculture to eat, and if shit hits the fan the poor outnumber the rich and the crop-killing pests outnumber the poor.