I coached for years in my son’s baseball and daughter’s softball leagues.
While I did not always agree with the calls (and some were egregious), I taught my players that the umpire might not always be right, but he/she was always the umpire.
Respect that.
Yup—in a major league baseball game it is very rare that an umpire gets every ball and strike call correct.
In addition we now know for certain (with the review process) that a significant number of other umpire calls are incorrect—again averaging about one bad call a game.
If managers went ballistic and created a scene for every bad call it would probably add an hour on to every game.
Good lesson for kids. Meanwhile adults should keep in mind that if the umps were actually good at umping, they'd be umping at a higher level than little leagues.