Matt - It is not as though the rules on this have never changed. Imagine how long a game would take if there were 8 balls per batter. We'd have 5/6 hour games and it would suck. If the games were shortened by changing the rules way back - it would still work - at least there is significant precedent for such consideration. From Wikipedia:
In 1880, the National League changed the rules so that eight balls instead of nine were required for a walk. In 1884, the National League changed the rules so that six balls were required for a walk. In 1886, the American Association changed the rules so that six balls instead of seven were required for a walk; however, the National League changed the rules so that seven balls were required for a walk instead of six. In 1887, the National League and American Association agreed to abide by some uniform rule changes and decreased the number of balls required for a walk to five. In 1889, the National League and the American Association decreased the number of balls required for a walk to four. In 2017, Major League Baseball approved a rule change allowing for a batter to be walked intentionally by having the defending bench signal to the Umpire. The move was met with some controversy.
Interestingly the rules changed from winning a game requiring 21 aces (runs) to 9 Frames (innings) in the 1860's as player skill improved to the point where scoring 21 runs was no longer a sure thing.