For me his statement is one of those things that is sort of not even wrong, like when people say humans only have two eyes and can drive a car therefore an automated driving system must be possible with only cameras. On the face of it, this seems like it could be true but of course it handwaves away the hardest and most mysterious part of intelligence and focusses instead on the easy bit that we already know reasonably well.
It's exactly like if someone said they had a secret formula to be an NBA superstar which is:
1. Be really tall
2. Be really agile
3. Be really good at basketball
Like yeah of course but all the hard parts are left out.
Is that not what humanity has developed from centuries/millennia of experience with all the approaches to child raising and education?
Engineering something trainable is clearly the difficult part given the entire conversation is about whether or not it's even possible.