The "sport" aspect of pinball has been long debated as well.
There is no question that pinball does not fall into the category of what most people think of as a sport. Most people's immediate reaction of sports is along the lines of football, baseball, basketball, hockey, soccer, running, etc. (sorry if I left out your favorite).
Arguing that pinball is like any of those is just silly.
However, in competitive pinball (which was what Lyman was referring to, not just playing pinball), being able to stand on your feet for extended periods of time, concentrate (there is a mental aspect to the game) and have consistent hand-eye coordination does take talent that not everyone has.
Some features in games of pinball can require 1-2 hours or more of play to achieve. (Example reaching Valinor on LOTR, or other very involved wizard modes). Some players can make a game last a long time-but the machines are designed for the 3-minute game on average.
Consistently qualifying and competing at the higher levels of pinball is not something that just anyone can do, just as not everyone can play in the major leagues or compete at the Olympics. Still people run around, toss and hit balls, etc. just like anybody can press start, plunge the ball and flip the flippers on a pinball machine.
Pinball may not be a sport in the sense that most associate with the word, but if just anyone could play pinball well, we wouldn't keep hearing about the same top pinball players over and over.