I totally agree with this and also about how it makes us vulnerable to people who cannot (and will not) understand the depth of the experience that someone who has undergone trauma has had to deal with.
Journaling about my trauma helps me, but only so much. There's a point where I feel the need to share it with a real human being. The healing that comes from sharing is so much more.
I have also found healing in reading other people's experiences. It gives me the motivation to not give up "the good fight" of healing myself and to overcome the past in order to thrive.
Having said that, the healing effect would have been the same whether the author wrote under their real name or a pen name. It would also be the same if the book/essay was written as a memoir or a work of fiction.
Maybe, that's a safer way to write about trauma - either under a pen name or as fiction. I am almost certain that it will bring similar benefits to the writer and readers.
Thank you for sharing your experiences.