> lack of compatibility between stacks in different programming languages
Well, that sure beats OpenAPI lack of compatibility between stacks in the same programming language.
I think the fact one can't randomly concatenate strings and call it "valid XML" a huge bonus over the very common "join strings with comma and \r\n", non-rfc4180 compliant (therefore mostly unparseable without human/LLM interaction) garbage people often pretend is CSV.