Hmm. I get a slightly different message from that second graph. He’s popping up less often on balls all up and down the zone, so it’s not specifically the high pitches that were presumably bedeviling him. He’s also golfing fewer pop-ups, and so forth. It may have been simply that for 3 years he was trying too hard to lift the ball for homers, and now he is just trying to meet it head on. Maybe?
So often we hear of players starting to hit more homers when they stop trying so hard for them.