Somehow the players association has gotten the power to control administration of games. The commissioner has the power to enforce the rules and to establish procedures for the umpires.
It's pretty basic. During a game only an umpire can call time out. It's NOT like football and basketball, which have a number of time outs to call. Baseball has devolved such that it's zero time outs has become unlimited time outs.
The other thing that the commissioner can do is to ban the managers and coaches from the playing field. This should include the first and third base coaches but if this proves a sticking point, let them stay out there. They don't slow down the game anyway.
The players association has boxed itself into a corner by fighting for many visits to the mound. This has been interpreted by the hysterical as having no definition. Does it mean manager/coach visits, catchers, infielders? The commissioner can directly ban manager/coach visits and indirectly keep non-pitchers off the mound by having the umpires NOT grant time out.
If the pitcher is entertaining teammates, the plate umpire can order him to pitch and, if he does not pitch, call a ball. If the catcher is visiting, the umpire can also call a catcher's balk, which, I think, would advance base runners.
Such ad hoc implicit player time outs would cease.
All this without changing the rules. Just using some basic common sense. How radical.