I think the following quotation is especially interesting:
"If a fly brain can now close the sensorimotor loop in simulation, the question for the mouse becomes one of scale, not of kind. Watch the video closely. What you are seeing is not an animation. It is not a reinforcement learning policy mimicking biology. It is a copy of a biological brain, wired neuron-to-neuron from electron microscopy data, running in simulation, making a body move. The ghost is no longer in the machine. The machine is becoming the ghost."