I get where you're coming from, but I don't believe overloading a data exchange format with too many dimensions of meaning is sensible. In XML, you can use tags

I get where you're coming from, but I don't believe overloading a data exchange format with too many dimensions of meaning is sensible. In XML, you can use tags, sequences of tags, tag attributes, and children tags; there are a multitude of ways to express the same thing. Following your approach, we could also count the number of spaces tags are indented with as an additional dimension: It's entirely possible to write XML this way and infer meaning from it, it's just not specified right now. I doubt you'd follow along with that. Let's look at the concrete reality we're dealing with: XML usage has declined, JSON (maybe supported by JSON schema) is ubiquitous. I'd be inclined to say the pendulum has swung a little too far in terms of simplicity - but overall, it's very clear why XML failed, and too few dimensions of meaning is definitely none of the reasons.