Man, McDonald's 1993 season looks like a Cy Young Award type year! He didn't even get any votes...
220.1 IP, 3.39 ERA, 171 Ks, 7 CG, 0.7 HR/9
Look at those same stats from the guy who won it that year, Jack McDowell. Not that different. Guess they really valued wins.
256.2 IP, 3.37 ERA, 158 Ks, 10 CG, 0.7 HR/9
In 1910 it was "only a fool uses his best stuff except when he really needs it, because you have to go nine every 3-4 days. Or more."
Today it's "use your best stuff all the time, or you're going to get the crap knocked out of you. But we'll yank you after five innings, and you only pitch once every five or six days."
Overall I'm not sure there's a lot of difference in how long a pitcher lasts.
Or... on smaller time scales Palmer vs Mussina. Four-man rotation and some high-pitch games and high-inning seasons, vs. never topping 250 innings in a five-man and more pitch counts. Palmer threw a few more career innings, but Mussina had three more seasons of 150+ innings. Mussina was never really injured, Palmer missed part or all of four years. And they had almost identical career W/L records.