The Cubs were upset with a called third strike on Ben Zobrist which ended the game.
Borderline calls are part of baseball, but the Cubs took exception to one that creates a loss.
If one play can turn a game, so can one pitch (especially the last one) goes the logic. If you can review a play at second base, why cannot you review a called third strike.
MLB has the pitch track technology at every ball park. The square in the corner of your TV screen is the alleged strike zone. But since there is a human element hardwired into the game, each individual strike zone is determined by several factors: the position of the umpire, the position of the catcher, the size of the catcher, how the batter stands in the box and to a lesser extent pitch framing. It is common knowledge that some umpires call high strikes while others call wide strikes. Pitchers are taught to adapt to the umpire calls during a game.
It has always been spurious for a manager to run out to home plate to argue a ball or strike call. A manager in the dugout has one of the worst positions to view the location of a pitch. At best, he can see the height of the ball but nothing else.
The only people who have a clear view of the pitch location are the catcher and the umpire. Next would be the pitcher but he is at a distance away from focus on the edge of home plate. Next, the batter who more often than not is concentrating on the baseball and not the imaginary plate glass strike zone at the edge of the plate.
The players with the next best view would be the shortstop (with a right hander pitching) and the second baseman (with a left hander pitching). Other than those individuals, no one else has even a remote chance to call a pitch a strike or a ball.
Technology is available to to determine linear location of an object. Tennis uses laser tech to determine if a ball crosses the end line. But that is a single purpose sensor. To have a similar feature calling balls and strikes, you would need horizontal and vertical lasers the width of home plate but also a grid sensor to determine that the ball crosses inside the strike zone. You would basically have to have two adjustable poles on either side of the batters boxes creating a horizontal grid and the front corners of home plate with lasers to make the square. There is an immediate safety concern with lasers close to ball players, and poles near the field of play (such as slides at home plate). In addition, the plate lasers can get covered with dirt which could create sensor errors.
But the fastest technology for depth and space perception is still the human eye.
A well trained umpire can adjust the strike zone for each batter. At the very least, he can be consistent in his calls. Baseball rules require a "fair" game for both sides, not a perfect contest.