OK, maybe I'm not really the guy to write about this. But I'm going to anyway.
I'm not a huge comics fan, and to the extent I like comics at all I'm more a Marvel than a DC type (and in the DC universe, I prefer Batman to Superman).
I'm also very much of mixed mind about Orson Scott Card.
On the one hand, I rate the first three Ender Wiggin novels among the great works of science fiction in general, and of English literature in the last half of the 20th century. Ender's Game is one of the great anti-war novels (especially given the rest of the cycle) -- and was also on the US Marine Corps' reading list because of its insights regarding leadership.
On the other hand, we're obviously political and social opponents. He's an anti-marriage, anti-family Mormon Democrat and I'm a pro-marriage, pro-family ex-Mormon anarchist. He thinks the government should be overthrown if it doesn't suppress marriages and families he doesn't like. I cheerfully agree that the government should be overthrown, but would likely fight to the death against his recommended replacement regime.
I can understand why some comic fans might not be hip to the idea of Card as Superman story author.
I can also understand why one artist would be uncomfortable partnering with another artist if their worldviews clash in a big way.
[all source material h/t David Klaus, btw]
But I think maybe everyone getting exercised about it is a disservice to all involved -- to the Superman franchise, to the fans, to Card.
HP Lovecraft was a racist, but the work was good.
Hell, Ezra Pound was a bona fide fascist, but lots of admirers say the poetry is good (not a big fan myself).
Robert Heinlein seemed a bit overly pre-occupied with propagandizing for consensual incest toward the end of his writing life, but most of his stuff was still incredibly good (the most incest-themed of hs novels, To Sail Beyond the Sunset, was fantastic; I thought The Cat Who Walks Through Walls failed as a story, but who doesn't have the occasional stinker, and wasn't he entitled to one after so many great books?).
My guess is that Superman fandom would be better off for having that story from Card, even while complaining about his heresies, than it is for letting those heresies bait them into depriving itself of the story.