Rob Manfred, the new commissioner of Major League Baseball, is 56 years old. That makes him a year older than the average television viewer of the last World Series. And that tells you all you need to know about the decline of our national pastime.

Manfred knows it, too, which is why he’s trying to speed up the game. When the baseball season begins Sunday, hitters will be required to stay in the batter’s box — except when time is called — and pitchers will be limited on the amount of time they can spend warming up between innings.

Manfred is also touting MLB’s phone app, designed to appeal to a tech-savvy younger demographic. But no rule change or Silicon Valley gizmo will rescue baseball from its geriatric doldrums. Put simply, our national pastime is past its time.

True, baseball still pulls in a robust $8 billion in revenue each year, up from $1 billion 20 years ago. But only 16 percent of Americans name Major League Baseball as their favorite spectator sport. Twice as many say professional football is their favorite.

And football generates a more truly national audience than baseball does. Americans will tune into almost any National Football League game, no matter where they live. But when a baseball game is televised, most viewers come from the teams’ local fan base. ...