I agree re the use of umpires, they are vital to the game.
Obviously we don't play baseball here but with cricket we still have umpires although with modern technology test teams are allowed two reviews if they think there has been grave injustice.
Once they are gone they are gone.
In the vast majority of cases the umpires are proved correct in the reviews.
The technology is only available in televised games, so most cricket isn't spoiled by Sky Sports. There was one game recently when (shock, horror!) the technology failed and the game had to revert to the decisions made by the on field umpires. It was quite nice to see the game played as it should be.