My ability to review and understand intent behind code isn't a primarily bottleneck to me actually efficiently reviewing code when it's requested of me, the primary bottleneck is being notified at the right time that I have a waiting request to review code.
If compilers were never a bottleneck, why would we ever try to make them faster? If build tools were never a bottleneck, why would we ever optimize those? These are all just some of the things that can stand between the identification of a problem and producing a solution for it.