Bicycles are the most efficient form of transport... at moderate speeds. At elite level speeds you are so far down the exponental well of wind resistance that you need meticulous attention to aero savings and sustained power output. All of the possible aero gains permitted under the rules are already accounted for. That leaves power output as the only avenue for gaining a competitive advantage. No other sport has the same combination of antagonizing factors at play.

He didn't say no skill, he said less in comparison with other professional sports.