They aren't accurate models of the human brain just as airplanes are not flapping their wings and cars don't walk on legs. Our brain's way of achieving intelligence is not the only one out there, even if LLMs aren't there yet.

Yes, we use now magnitudes more oil than we used to 120 years ago. But back then oil was used for cooking and lamps, while now it is used for so many more things. Same goes for data. It is the new oil :).