I don't believe he was necessarily "dominating." Before being called up in '22, he hadn't even reached 60 innings in AAA. His bb/9 was 3.68. He had a successful half of a season. The year before, he had a 3.87 ERA between A/AA. I think he was called up too early, under a bad pitching coach and wasn't quite ready to be the guy they wanted him to be. He went from a 12 k/9 in MiLB to 8 k/9 in MLB while keeping a high bb rate. He just never really learned how to pitch. Whenever he gets into a stressful situation, you can just stick a fork in him. At some point, it's no longer on the coaching, but on the pitchers themselves.
Fitts, Dobbins and Buehler have all been more impressive than we thought they'd be, but I don't see many people jumping to give Bailey credit there. I'd say the same with Chapman, Weissert and Wilson. Maybe Bello stinks this year because he's just not as good as we thought he was going to be. Maybe he's just a #5? Maybe Houck is just the starting rotation/reliever question mark that we had him pegged for going into 2024 and not the All Star we saw last season? We're lucky Bailey was able to get that half of a season out of Houck.
Coaches are fungible. Fire Cora, Bailey and Fatse if you really want. However, I don't think it'll change the direction of this team in any positive direction this season. It's almost always on the players and who picks the players. The coaches are just low hanging fruit IMO.