Elon Musk said during the panel at the Asilomar conference ("Beneficial AI 2017 Conference"):
[...] Everyone is already superhuman. And a cyborg. The limitation is one of bandwidth. We're bandwidth constrained, particularly on output. Our input is much better, but our output is extremely slow. If you want to be generous, you could say maybe it's a few hundred bits per second, or a kilobyte, something like that, output. The way we output is, we have our little meat-sticks, that we move very slowly and push buttons, or tap a little screen.