Board Thread:Wiki-Related Discussion/@comment-32423680-20181206163106/@comment-26967699-20181207050054

The Wiki sees him as real Walt Disney.

In 4x16, August only mentions the last author as "a man named Walt", and that's it. In 4x21 however, we see the Apprentice talking about how the latest author (without giving out his name) passed away on the day of real Walt Disney's death.

And if you check the List of Minor Characters page, you'll see that he is named as "Walt Disney", even though it was not expressly said that way. So yeah, the latest author before Isaac is the real Walt Disney according to Wiki.