There are certainly several valid reasons to use a pen name. And I think it is a personal choice. It works for some and not for others.

I wrote under a pen name for a few months as an experiment. I wanted to write on topics I normally wouldn’t. Hoping to shield myself from any fallout by using anonymity. But I discovered that it didn’t really enjoy the experience. And I started liking the persona/character I had created more than sharing my opinion on controversial topics. So I stopped publishing under the pen name. But I kept the character as a fictional character who I still write as, but publish the stories under my own name. Here is a more detailed version of my experience if you are interested:

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