This is a good point. Umpiring is under the microscope and having that little box on the TV screen that is not 100% accurate doesn't helps either.
Plus, you have pitches regularly coming in at 95 MPH and higher and breaking pitches and changeups that move upwards of 60 inches at times. That's a tough gig. Then you miss a call that is one inch off the plate, and the fans are screaming that you need to lose your job.
I've seen multiple times this year and strike being called that looks low on the TV box, but when I went into statcast that uses the actual strike zone for the player, it was a strike.
I agree though with the folks that say the bottom tier of umpires should be placed on probation" and if they miss too many, that they either need to go back to AAA or they need to be "released," just like when a player can no longer perform at that level.