I say it's about time - though full implementation of a robot umpire in MLB will take some time. You still need the home plate umpire to call out the balls and strikes, to judge plays in the vicinity of home plate, be the final arbiter in disputes, etc. However, none of these guys really know if a ball catches the edge of the plate. Let the professionals take that on with 100% accuracy - the robots!
https://www.espn.com/mlb/story/_/id/35434317/sources-all-aaa-parks-use-electronic-strike-zone-23
https://www.espn.com/mlb/story/_/id/35434317/sources-all-aaa-parks-use-electronic-strike-zone-23