How YAML got so popular is a mystery to me. It's a huge pain. Then again, I've given up on fighting it, and simply learned how to use it, since I can't escape Kubernetes anyways.
Also people are mostly arguing for code vs markup. yml, json, xml etc are all the same. Yml just happens to be more compact which helps with visibility in a big file.
It's good at being human-readable. It's basically json with indents and comments. What other configuration format is out there that allows for tree structure and it's easier on humans? (not XML or json).
JSON has some surprises and a lot of limitations, but is so much simpler than YAML that it seems worth putting up with them.
If we consider high composability, non-ambiguity, clarity, expressability (even a word?) as aspects of "human readability" - YAML doesn't go very far in the scale across many of these. A language, with slightly more appealing (yet non-limiting for programmablity) declarative constructs seem very helpful for needs like this.
It would be great to see any spider-web-graph of all these solutions across those aspects and thus help someone to take a wiser decision.
Yaml is just like xml. They all kinda look similar, but can have big and important differences