I work as an analyst for a MLB team. Bad calls are frustrating, but automated systems are not foolproof. It's been a few years, but there have been MLB games where the system is down completely. Can you imagine having to delay a game to get a tech out there? Woof.

But really, I think we give umps an apple watch or something that buzzes whenever the ball is a strike. That data could be available very near real time. And then, once the umps get real time feedback, you never tell anyone you're doing it. The umpires association would be down for keeping it under wraps, as it keeps the robots away, the old school "human element" folks would be happy, and the calls would get better!