Earlier quoted context omitted.
Cross-gender pen names are an common tradition. Have they also condemned the Bronte sisters or George Elliot or George Sand for creating a different gender persona for their writing? Or JK Rowling and Andre Norton literally changing their name for marketing purposes so that their gender would not be apparent on the books cover while they were still unknown as authors?
Men outrank women on the privilege stack. A woman adopting a male persona is "punching up"; a man adopting a female persona is "punching down".
However, the women I mentioned (like Bronte sisters) were not "punching up", they were not "punching" anyone in any way whatsoever, the choice of persona has no relation to some kind of aggression, they're simply choosing an arbitrary identity and that's it, there's not the slightest moral concern about this act, it's a well-established (and frequently used) writer's right to choose a pen name or persona and there's not the slightest thing wrong about that, no matter which group is adopting which persona - and the same applies for those three writers choosing their pen name. "Punching up" is considered less aggressive than "punching down", but adopting a persona is not even on the same scale, there's zero aggression about that.
On the other hand, attacking writers for their choice of pen name is punching. In this case it is the less-bad version because it is "punching up", but it is a form of bullying; a much more aggressive act than what those three writers have done.