As a writer and reader I disagree with this. Perhaps if you are writing for a scientific journal or business report, long blocks of text can seem like you have a lot of info. Generally speaking, especially in fiction and non fiction i think unbroken pages of text will best case scenario bore a reader, worst case scenraio burden and overwhelm them with a lot of info so the feel daunted about continuing.
"Autobiography" means a biography of oneself, that is, the author is describing their own past and their own life.
When you describe your own life, typically you would write it in the first person ("I") and this is also true for Barrio Boy.