Separate file management from DITA publishing
A DITA publication is more than a folder of XML files. Maps organize topics; references and keys connect reusable material; filtering produces variants; and transformation creates the reader-facing output. Uploading the source files to a document library does not by itself perform those operations.
For example, DITA Open Toolkit’s HTML5 transformation generates HTML and a table of contents. An implementation still needs to decide how that output reaches readers, how its assets and links work, and how subsequent releases replace or coexist with it.
SharePoint can participate in that architecture as a source repository, file destination, or entry point to another service. The question is whether your proposed implementation provides the complete DITA publishing and reading workflow, rather than whether it can store an XML or PDF file.
