What's wrong with disliking a character?

Genuinely curious because I'm really glad characters like Ruan Mei, Jade, Topaz and Dr Ratio exist despite having less thank likeable traits. It makes the cast more dynamic and the overal Honkai universe more...unique, you could say? Just imagine if everyone was good and friendly with Trailblazer. Characters will get boring and repetitive real fast.

This suddenly occured to me after Aglaea came out and people having 'mixed' opinions about her. Just like some other controversial characters, we have those who sympathize with her actions and understand where she is coming from and those who dislike her no matter what. These two sides are at odds because the former is accused of "excusing behaviour" where the latter is accused of "being too sensitive/don't truly understand the character." But, what if you have understood the character and sympathize with their background but still dislike them?

There are other media with hateable characters but have such damn good writing that the story is nothing without them (characters you love to hate type of thing). I just want to understand the clarity behind the cotext of these discussions. Just because people complain about controversial character ≠ they want less of those traits and sympathetic actions ≠ need to be liked. Restricting to just likable traits/likability purposes closes the door for creativity and good writing. I hope one day hoyo can fully embrace an unapologetic villain who fully embraces their terrible self (Dottore from GI).

Tdlr; disliking a character might be a sign of good writing on dev's part