I would not call machine-produced XML at all human-readable.
Of course, I suppose some amount of human-readability is pretty important. It's why textproto became a de-facto standard for protobufs.
They are quite often not, but the. XML does have style sheets which make things a bit easier since every browser can render an XML into a human only readable format that way.
"Human readable" in XML lingo means, actually, "Human readable after transformation". Or: add some CSS to it and it's easily consumable.