Interview with a pitcher and a catcher in the Atlantic league on fangraphs.
https://blogs.fangraphs.com/ef...-and-catcher-report/
Unfortunately the catcher sound quality isn't great due to phone but neither really likes it. They said it not only call strange pitches as strikes that real umps don't call but it even is inconsistent batter to batter which is exactly what it should avoid. The pitcher says he thinks it will get better but right now it is not ready. Not sure if that is perception or reality.
Pitcher also says robo ump favors tall over the top guys with big straight down breaking balls but side to side pitches like cutters and sliders and lower arm slots are in a disadvantage. That makes sense because real umps call a shorter and wider zone than the real zone so robo ump gives more strikes up and down and less in and especially out than real umps.
Stats however didn't change that much with robo ump, walks slightly down and Ks and runs basically the same so maybe in the end it all cancels out somehow and maybe those two guys really just had a different perception.