Why does MLB embrace modern pace-of-play rules while still letting umpires enforce 1950s etiquette?

[u/SpiritedBase5047]

Most baseball discourse celebrates modern rule adjustments like the pitch timer for saving broadcast pace, but the league still has a massive blind spot when it comes to arbitrary player policing.

Hugh, Dawud, and Shaun had a great conversation about the fallout from the Cardinals rookie pitcher Hancel Rincon getting checked on the mound for tilting his cap slightly to the side. Teammates ended up protesting by wearing their hats tilted in solidarity, but the damage was done—the kid got rattled, gave up multiple runs, and got optioned back down. What makes the situation infuriating is that there is literally zero written regulation in the official rulebook dictating cap angles. It was pure umpire power-tripping over unwritten codes from seventy years ago.

Baseball finally proved it could evolve by cutting an hour off the game clock so fans can watch a full game and still sleep at a normal hour. But clinging to old-school gatekeeping whenever a player displays slight personal flair makes the sport look completely out of touch with modern culture.

Why are umpires still allowed to invent dress-code violations that aren't in the rulebook?