Neither.
Bad writing and horrible editorial mandates.
But unfortunately, that's now canonically part of their characterization.
The Scarlet Witch. A Mutant Pox On Her House.
Medusa. May Her Hairline Edges Forever Be Thin
I Don't Hate Either Of These Characters! #MakeAmericaHumanAgain
Hank McCoy Is The Real Enemy
Neither.
Bad writing and horrible editorial mandates.
But unfortunately, that's now canonically part of their characterization.
“Have courage and be kind. Where there is kindness there is goodness, and where there is goodness there is magic.” ― Cinderella
When Wanda was talking to Rogue, it was with Rick Remender's voice. Based on what I have heard, he seemed to have a big problem with the concept of mutants in general, and it has shown up in his writing. Wanda was basically used to give voice to his issues with the X-Men. Why he was asked to write for them, I don't know.
However, while Wanda was retconned into being under control of the Life Force, it didn't tell her to say No More Mutants. If Scott is to be held accountable for killing Xavier, she has to be held in the same way. She did it to hurt Erik, who she thought was her father and hated. In that moment, she wanted to hurt him badly for caring more for mutantkind than for his own kids, and destroying mutantkind was the way to go. In her subconscious, mutantkind was a symbol of her toxic relationship with him, and she hated it.
But, Medusa is benefiting from the pain and tragedy of mutants. Sure, mutants are dying, but her people are thriving and multiplying, and that is only a good thing. Now, the mutants are fed up and fighting back. She is being asked, "Choose: either the mists go, and you find a new way to get Inhumans, or the mists stay, and you end up responsible for the extinction of an entire race." She basically chose the latter. So, Medusa is worse than Wanda.
The Life Force explanation didn't replace the breakdown. Wanda had the nervous breakdown before going to see Doom. She wasn't thinking straight when she chose to see Doom. She then got possessed by the Life Force and was not longer controlling her own actions.
Hank. Always Hank.
"What would you prefer? Yellow spandex?" – Scott Summers, 2000
I wonder what will happen if these two clash? No more hair vs gas you mutant though too bad she isn't a mutant anymore. Anyway it seems hard to hate any fictional character so much. Certainly the mutants are somehow marvels version of the wandering people although they don't really seem all different from the rest of the super powered folks. The Thing and the Hulk are both there along with the mutants for the treatment they receive although more so the hulk. I remember one story where reed was hated for it comes out he purposefully neglected to have proper shielding so they could gain powers. I wonder if there were some mutants who were glad to be rid of their gene especially if it just deformed them without granting them powers when sw cast the. spell? Having a normal human body would be a boon for those whose mutation caused harm to themselves and others although it doesn't excuse those deaths which were caused directly or indirectly by the spell.
I think comparing Jean and Wanda in the breakdown/retcon department is a masterclass in what works and what doesn't in terms of rebooting a character and having the audience accept them back. With the two of them Marvel essentially tried to make the same dish while using two different recipes. Both are beloved characters, but Jean does not get the hate Wanda does over the past genocidal sins. Even people who don't like Jean don't harp on her for it. If anything they argue that her return ruins the Dark Phoenix Saga in retrospect. But even if we ignore their eventual retcons the initial stories were approached completely differently.
For Jean her dark turn was a gradual one, and both the audience and the X-Men knew an outside influence was screwing with her because they watched it happen in real time. We knew Mastermind was behind it because we saw his manipulations from the getgo.
Wanda, on the other hand, was fine one day and bonkers the next, with no sign of foul play involved. And it didn't help that Dr. Strange came in at the eleventh hour to exposit that her powers in fact did not work the way we'd been told they did all these years and that mixed with her tumultuous life meant she was doomed (heh) to be a ticking timebomb as is.
When their respective ends came about Jean took her life to make up for what had happened, while Wanda reset the universe (minus the mutants), wiped her own mind and sent herself off to the mountains of Europe to live in peace. Jean's story finished as far as anyone knew while Wanda's was put on hold.
Jean also benefitted between death and ressurection from the Phoenix existing within Rachel and showing that it was its own entity that could do just about whatever it wanted and could magnify the personality of whoever it resided in. But I don't know much about the force that Wanda was plugged into, but tieing that to Dr. Doom who had nothing to do with the original story definitely was a tad too convenient narrative-wise.