Don't know but a single neuron as a computation unit is far more complex than an ANN [1].

[1] https://christofkoch.com/biophysics-book/

You're totally right that we're far away from brain-level efficiency, but I'm just saying any efficiency gains we make towards small models will likely be felt on large ones as well, and we'll all move the goalposts to what the frontier can do. Hypothetically, getting GPT 5.6 performance in a 30B model would be amazing, but just imagine what you could do with a GPT 5.6-sized model at that point.