Velocity and xBA are great measures of a "quality at bat." If you hit the ball 95+ mph, that's a good AB. If it happens to be right at a fielder, well, you can't control that.
I would add the coaching staff to the list. Whatever the coaches are doing to prepare the pitchers and hitters is not working. Maybe that's on Rocco, but I think it's much more complicated than that.
"Jorge Alcalá hasn’t pitched well against lefties, who are batting .362/.455/.723 when he’s on the mound." https://theathletic.com/2567965/2021/05/05/latest-bullpen-failure-adds-up-to-another-difficult-loss-for-twins/