Since the Pagebuilder is used from within the pages themselves, the end user would have to edit their content by the Pagebuilder blocks.
I don’t know how I would use Pagebuilder to setup the layout part and then allow the end user only access to the content within.
For my web projects, I’m always thinking in terms of letting the users edit their own stuff when I’m done. I don’t like building something where they require a developer to make changes. Pagebuilders don’t really allow this separation of content from template.