Maybe-- but so what? It's not like it's hurting anyone.
...unless it's hurting you. Don't hurt yourself.
If you do: don't do entire same legal name so you're easy to dox(Firstname Middlename Lastname is pretty easy to find compared to just using Firstname and changing the rest or using a nickname), don't spell it the same as your actual name if you have an uncommon name, and know that if you get doxxed, people will probably use it as an avenue to make fun of you (but this probably wouldn't be the suckiest part about getting doxxed).
Also if you ever show it to anyone who does know your real name, they'll absolutely know/think there's some level of self-insert going on.