No, the current limit is not physical, it's that nobody has any idea how general intelligence works.
You do not, in fact, get general intelligence by accident by throwing a lot of connections in one place, just like you do not get a human just by throwing a lot of organic molecules and water in one place.
You do not, in fact, get general intelligence by accident by throwing a lot of connections in one place, just like you do not get a human just by throwing a lot of organic molecules and water in one place.