I have delivered XML data products comprising terabytes of information in (when I last checked) more than 800 schemas to companies around the globe, and people who have a rosy view of XML are using missing how it usually works in practice. XML is extremely heavy and brings a lot of half-baked ideas, and consumers are almost never flexible in ingesting the XML. It means teams wind up supporting insanely convoluted schemas that customers will never migrate off of.