Make the pitcher unimportant again.

Pitchers are not players. Replace them with a pitching machine.

The Pace-of-Play Problem Began in 1884
by Joe Sheehan - April 13, 2017 fangraphs.com

Let’s back up. Baseball, as evolved from various stick-and-ball games in the 19th century, was originally a contest in which the pitcher’s role was similar to that of a slow-pitch softball hurler. His job was to kick things off by offering up a ball that the batter could whack into the field of play, where the real business of playing baseball happened: running and throwing and fielding and even throwing the ball at a baserunner to record an out. The pitcher was the least important player on the field in the game’s early days. There were, in fact, no mechanisms to force the pitcher to give the batter hittable pitches; it was just considered his job to do so. Batters were even able to request high or low pitches, the better to fit their swing.
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