Thing is Gaiman pissed off all feminists with the SA allegations so of course he has disappeared from the online world because the cross over between Neil Gaiman readers and SA-appologists is very small.
Whereas a sect of the feminists support her gatekeeping opinion that the only thing that can describe if you're a woman is being born with a cunt. This one very vocal audience is not unified.
On top of that Rowling is more mainstream than Gaiman is and the general public is more willing to ignore the mudslinging world of gender politics and not get involved if it means more content from a popular mediocre scribe.
yeah, agreed - Gaiman's fans are far less willing to tolerate his SA, HP fans are more general public and transphobia is more socially acceptable than SA.
Basically this post is essentially saying, "it's a shame transphobia is so acceptable to people"
Also, I think that the fact that Harry Potter was a big part of people's childhoods made them more reluctant to abandon it when the creator turned out to be garbage. See: Nintendo.