2 of the examples were neither from a main character for starters and never in the story were never supossed to be seen as a big deal, unlike Erza's father and I already explained Judge.
Now, did One Piece ever had a God of War that was two-shotted by the main protagonist? Did it had the 5th stongest human mage of the continent being defeated by a degenerated former antagonist that had to quote the main character's line? Did it had a bunch of secondary characters that pratically does not exists to be there just so they can show how much important the main cast is and show how can a 7 year "timeskip" witout progress can be tense? You can't just compare 2 series that are in very different tiers.
Such as?
Your reasoning with the Vinsmokes is not a good enough reason and it doesn't excuse Oda writing them as shallow as he has been doing. Super soldiers as they are, they're whole drama is incredibly forced due to how artificial Oda writes them. For example –
- Of course Sanji has a douche-bag father with no redeeming features and considers him absolute trash because he's weak. He's never considered Sanji his son. The only thing he requested from him when he left was that he dropped the Vinsmoke name because he's, again, trash. And of course he stabs through his own men just to get in an attack. I mean... come on! How much more evil does Oda need to write this character before he's satisfied with his work? It's just laid on way too thick, way too exaggerated and way too one-note.
2 ) Of course, the family is conceited because they're, you guessed it, royalty. Thanks for telling us that flat-out. But of course Niji continues to beat this into our head by not wanting to finish his plate of food, this being here because GASP Sanji is there so what better way to show off someone being jerk than by doing what Sanji hates. Oh but it doesn't stop there, of course then we need to see Niji attempt to strike the girl cook who made their meal with a friggin' plate which of course triggers the other thing that pisses Sanji off - violence to women. Then of course they're proclamation about being royalty which of course means they need to act in the most obnoxious way possible because reasons. Oh, and they also like to talk about Sanji possibly dying at sea because they're asses and need another thing to prove that they are. Apparently. Smh. NOTE -- Leaving out the cook girl being beaten because we don't truly know who did it yet, but if it turns out to be one of the brothers, just chalk that up as another unnecessary addition to make them seem more predictably evil.
3 ) Sanji's new backstory is interesting when its talking about how they've been genetically modified, but the whole plot on how that turned the brothers into heartless monsters is groan-inducing. As is all the panels with them of course beating up Sanji and calling him names because, THEY'RE EVIL MONSTERS WITH NO HEART! FEEL BAD FOR SANJI NOW, DAMMIT! He's locked up in a dungeon by his own family because he's useless and his father looks away and doesn't help him when he's being beaten, DON'T YOU FEEL BAD YET!?
They're caricatures. Written that way solely so you can feel bad for Sanji right away and be satisfied with their eventual defeat and/or redemption. It's true that there's still room to grow for them since the arc isn't over yet, but what is available right now is plenty enough for me to call them one-note characters. All of them except for Reiju, that is. She's fine.
As for other one-note characters... pretty much every noble/world noble in existence (especially in the Luffy, Ace, Sabo flashback, all those nobles were extremelyyyyyy one-notedly evil for the sake of being evil. Just to prove how corrupted the wealthy are. From their complete disregard of human lives, to caring so much about their social status that their willing to mistreat their son. It's all on the nose in the most extreme form), There's also the other examples the other poster listed.
Anyway, I tire of this so I'm just gonna leave it at this -- I know FT fucks up wayyyyyyyyyyyy more often than OP and with far more terrible flair. Those scene you listed do indeed make FT worse than OP. But when it comes to THIS scene - a character introduced just to act stereotypically evil with no form of actual thought or reason, just to make you feel bad for another character - OP has done this and with no complaints from some of you people complaining about other series doing the same thing. So it's just kinda hypocritical, is all. But that's the nature of anime/manga fandom, I suppose.