Earlier quoted context omitted.
Humans are also extensively pretrained by billions of years of evolution, so by starting from scratch GPT is admittedly disadvantaged from the get-go.
But the human genome is only 3 gigabytes and the vast majority of that is unlikely to be encoding brain structure.
The lambda calculus (a system we know is capable of infinite self-complexity, learning, etc. with the right program) can be described in a few hundred bits. And a neural net can be described in the lambda calculus in perhaps a few thousand bits.
Also, we have no idea how "compressed" the genome is.