I'm starting to feel conflicted about reincarnation stories of characters that were origin...

Also the Duke, he was also the one that wronged her and cast her into the life of abuse, whether she was the real chloe or not. But we dont see him being accountable for it other than getting a little jealous at the prince. Because its isekai, if you are the MC and ML, the authors will write in total favor of them and never address anything that might give them a headache to think about even when things are morally dubious.

Because this was made for entertainment, a cheap shot at getting attention from the readers and the gratification of revenge. Thats why it always start out as very controversial, a modern girl becoming an unloved wife or a villainess. Every plot is different when it starts out, but they all become the same lackluster indulgent daydream at the end. Meeting minor villains, always triumphing over small issues and punishing the minor villains unfairly and finally being rewarded with lavish things by a husband.

Another manga is Villainess turns back the hourglass. She was someone that was evil enough to pull out a tongue from a maid she didnt like. Sure she was encouraged to become evil by the previous protagonist. However, she was not free from blame as she was the one that chose to be evil, only knowing to change after her reincarnation. The story is interesting and I was interested to know how such a controversial plot will play out in redeeming an irredeemable villain. But no, its the same,

things go her way all the time,
MC always a step ahead of the minor villain,
MC torments the minor villain and that leads to her death,
MC meets a rich prince that dotes and lavishes her with gifts etc etc.

No addressing on the complexity of her past actions as an evil woman and redeeming herself and improving her world view, everything was blamed on the minor villain and the MC becomes the same thing the minor villain was in her wish to destroy the minor villain and her entire family. Only the writing changed it and make it look like MC is right all the time. The only saving grace was that the minor villain did incite a rebellion that led to her house falling. She was already going to be executed for that and not cos of the MC. Butttt the MC saved her and framed her again just to have one last laugh, and this was just beating a dead horse just for readers to be mindlessly satisfied.

As long as the story satisfies the reader by making sure the Main leads are always safe and ahead of the game and the minor villains are always unfairly punished for slighting them, the authors can write about stories with complicated openers like transmigration and court intrigue without having to think too much about how lacking the plot is as the story to progress. Because the viewers are all here to see the MC getting favored and spoiled by the plot, not the quality of the story. If the plot was truly deep, it will make isekai writers have a harder time trying to actually write a compelling story that makes sense

You see one nobility isekai, you've basically seen them all.

I don't think so, the duke wasn't the reason she was treated like trash. It's because of her! She was a liar who bragged about things she didn't have, avoided her responsibilities, blamed others for her own mistakes, and falsely accused those weaker than her of things they didn't do. Nobody likes this type of person, even the kind maids would be blind to follow someone like that who could easily blame them when she made a mistake. The original Chloe deserved punishment and that kitchen-maid deserved justice for what happened to her. But like you said, the author just wants to avoid any unfavorable looks toward the MC and made that kitchen-maid to be forgiving. While the other smaller villains deserved punishment even after repenting like those who followed the head maid.

Also the duke is not drastically different from before it's just that Chloe is the one who is different. When he tried reaching out to the original Chloe she was so uncomfortable around him and purposefully avoided him, so he decided to give her space, but when she finally reached out to him he was quite welcoming.

Other than that, everything you wrote summed up these types of stories perfectly.
I found it interesting at first, but the more stories I read the more conflicted I became. Some manga/webtoons like the "Miss Not-So Sidekick" and "Cheating Men Must Die" show how messed up these types of stories are.

I really really dislike inconsistent characters and the system can be when it comes to the MC. Either by having the ML behave completely out of character when faced with the FL (as if he was charmed with a spell, it was mentioned in "Jishou Akuyaku Reijou na Konyakusha no Kansatsu Kiroku" I've seen it happen in many manga/webtoons), or the FL overlooking all the terrible things the ML did just because he turned a new page. Although now we're seeing it with female leads as well.

With reincarnation stories of bad characters, like this one, those who originally had a bad character, they don't really deserve a second chance and I can't see how the people around them just ignore all the terrible things they did in the past so easily, authors just make them so forgiving to the MC to avoid unfavorable discussions.
While with re-born stories, like Doctor Elise, the difference between her before and after character is like the difference between night and day. People can change to some extent, but for her to go from this overall possessive, jealous, short-tempered, and evil character who hurt others to this empty-headed, shy, innocent, and kind-hearted person doesn't make sense to me. At least have her be this quite and mature girl who went through a lot in life and learned from her mistakes.
For "Villainess turns back the hourglass," you're completely right! I haven't finished reading the novel yet, but one thing I admire about the story is that the MC's character is consistent from beginning to end. She WAS and still IS this evil selfish woman. So I would give them that at least.