Claremont was the one to retcon Polaris as Magneto's daughter right ?
Actually that wasn’t the case either direction. Claremont is the one who set Wanda and Pietro as Magneto’s kids, and established the Holocaust storyline (which is part of why I say he was good for SOME things).
I can’t remember who did the retcon of Lorna not being Magneto’s daughter. I’m too lazy to go look it up right now. It was shortly after Lorna’s introduction, and before Claremont.
The retcon to restore her as Magneto’s daughter was a slower build with multiple hands.
If you had to credit just one person, it would be Chuck Austen, because he was the first to explicitly say she’s his daughter after that past retcon.
However, Grant Morrison wrote the issue of her found in the Genoshan ruins, during which she called Magneto ‘daddy’.
Various writers wrote her on Genosha prior to that event, filling a daughter-like role in all but name.
Mike Carey wrote the X-Men Legacy issues that reaffirmed Lorna’s parentage about a decade after Austen.
A couple years later, Peter David added more affirmation with the origin story of the plane crash (yes, X-Men characters love plane crashes)
So whereas Lorna not being his daughter was the whims of a single writer and editor team, restoring her as Magneto’s daughter was a multi-team and multi-decade project.
One thing we badly need to watch out for, though, is Lorna being reduced to a plot device and arm candy for other characters, mostly men. Decades of Lorna treated that way, mostly for Havok and heavily by Claremont, makes her more vulnerable to that. X-Men 97 is currently falling right into it while trying to make Lorna look superficially cool to cover it up.
X-Men 97 refusing to acknowledge Lorna as a Genoshan genocide survivor is a critical example of this. A lot of people that want to give the cartoon a pass seem to think it’s just some tiny insignificant element. But if the team is so ready and eager to cut out the single most important thing about her history as her own character, then there’s really no hope for their conception of her. It’s the reddest flag.
People use the Bechdel test as a measurement for conversations. But if you apply it to overall plot, X-Men 97 is failing badly. That show presently defines her as having been on Havok’s X-Factor, as being part of Magneto and Xavier’s personal drama, and as being Bishop’s potential girlfriend.