I'm only a casual baseball viewer, but balls and strikes are so easy to see on TV and the umpires miss a lot of obvious calls. It makes a lot of sense to make this a game mechanic that is managed by the machine, rather than requiring humans to judge this. Humans are still judging baserunning and the more subjective aspects of the game.
I'll also note that MLB isn't doing the "replace umpires with software". Teams get 2 challenges to use, and those are adjudicated by robots. The initial call is made by humans and a human has to say "use my finite resource to engage the robots". (I would just make all calls by robot and have a challenge to have humans look at it, but whatever. Baby steps. We know where this is going.)
The NFL uses the same technology to measure first downs now. No more carrying the chains out to measure by hand. But the officials still spot the ball where they think they play ended, so the computer isn't doing anything important. It's just doing the tedious part.
Nobody is losing their job and no fun is being removed from the game.
