Policy about Author's Names in Posts

I read almost ‘all’ interventions about the long disputed question: “how to change Authors’s name in Posts.”
Nobody ever said why you must have the Author’s name inside the list of your registered Users!
For example, imagine I have a literary blog, and I have a short script from Somerset Maugham, with the right to publish.
If I want to give to Somerset Maugham the right contribution as an Author I must:

1. Create a User with the “nickname” Somerset Maugham.
2. Find out an email (that cannot be fake) for Somerset Maugham
3. Give to this fake User the Author‘s role

All this is absolutely out of mind!
Any idea why WordPress has not a simpler method to change the name of Author in Post?
Thank you.