I really havent seen anyone complaining about the petals as visual metaphor tbh.
Not even as visual metaphor, I don't even think they necessarily look that bad when considering the scene they exist in, which is usually contrasting with a black background.
All i see are people hating on the full body aura which they have every right to.
Don't think that was as bad this episode either, even the comped one. The aura for the most part was mainly just a bit of bloom on Luffy but mainly surrounding him. Outside of Luffy's limbs in a few cuts, it was usually pretty easy to follow along with. Unlike last episode where the aura ruined the shape of the effects, they clearly defined where it existed.
It looks like shit. And them saying "the screen is too yellow and bright" imo is them pointing out how unclear and bad the comp was espcecially during Shida's scenes.
For the most, it wasn't that unclear. There were some scenes which were too bright, namely the scene with Kaido being hurled back, but not a ton of action was going on in that scene anyone and most of the shots of Kaido were long distance.
This shot in particular is probably the worst application of the aura to Luffy's body in the entire scene.
Stuff like this has glow to it, but the clow is surrounding Luffy, and the layer of white and the black lines still provide a full two layers of seperation that make sure Lufy isn't lost in the aura.
Stuff like this for example has glow, but I'd hardly say the aura is destroying the detail here.
Hell, even in this scene, Luffy is pretty visible and stands out pretty well.
This is a bit to yellow on the arm, though that is the point of the scene, and it does bleed across, slightly, but its hardly obscuring the details here. Its not like even the ryuo aura's which are far more involved.
This is probably the one scene where it went a bit too over the top.
I think your also ignoring the fact that people aren't selectively choosing scenes here. Sugita's scene is just as criticized despite the fact that the execution for the compositing of that scene is spot on, and its also, a lot more yellow than Shida's scenes for the most part. You could definitely argue the yellow is a lot better intergrated in Sugita's scene, but do you think anyone else differentiates between the compositing in Shida's scene versus the compositing in Vincent or Sugita's scene?