It's probably more the former than the latter, but this has gone on long enough that I'm definitely a bit concerned. Nothing specifically has broken. As the season has gone on he's still chasing less than the MLB average, his exit velocity data looks solid, and he's not hitting a stupid number of groundballs (though more than he typically does). The strikeout and walk rates are bad since his hot start, but the components that feed into those are fine, so that may least is very unlikely to be permanent. What has fallen apart are his numbers against non 4 seam fastballs. Since Seiya got back from his IL trip he's been horrendous against cutters and splitters, and bad against sinkers. He's also been bad against curve balls lately after crushing them early in the year. Glass half empty is that the league has found an approach that works against him. Glass half full is that he's simply adjusting to the stuff in MLB still. Japan has lower velocity generally, and so the mid-high 90s sinkers and cutters that are uncommon over here are nearly non-existent over there, and he's seeing a lot of this wizardry for the first time. But the fact that he's still doing damage on 4 seamers would indicate that high velocity more broadly is not going to be a permanent barrier for him. I think he's at minimum a solid 2 win player. The peripheral offensive numbers even if we take out his hot start point to a league average-ish hitter. The defense is legit and has almost never been in question, his numbers are bad but that's mostly because he was total ass early in the year as he was learning new parks. I'm not worried about him going full Fukudome on us. That said I'm less confident he's a star than I have been at any point yet He kinda needs to come out of the gate blasting next season for me to hold onto that hope.