Im not a Castro fan to say the least, never really got the buzz around him, but saying he is bad is just crazy. I know this is a troll post but the point (as trolly as it may be) deserves some discussion
His approach at the plate is terrible and he seems to give away ABs at least once a game. His contact rates (both inside and outside the zone) are down quite a bit and his swinging strike percentage is way up. But he is still hitting 270 (its the OBP that is the worry) with a BABIP that is below his career average.
Fielding wise i think it just comes down to concentration. I know this is kinda a Hawk Harrelson explanation (just hope he has the "will to win") but with Starlin he appears to lack focus a decent amount. Stats wise he ranks about average to slightly below average defensively but he passes the eye test at least in my opinion.
For a 23 year old SS i think we can live with some of the mistakes and hope he grows into what he could be if everything clicks and the approach changes. a 3% walk rate isnt gonna cut it