A respected senior engineer once told me "all configuration is code, if it modifies the behaviour of software, it needs to be testable"

Yaml is huge unintuitive PITA, I recently spent multiple hours figuring out the best way pass CLI arguments to a k8s cronjob via yaml. I only managed to solve the weird error messages after I stumbled upon the stackoverflow post linked in the webpage https://stackoverflow.com/a/21699210

> There are NINE (or 63*, depending how you count) different ways to write multi-line strings in YAML.

Why is it used so much? Tooling? Stockholm Syndrome?

The same reason visual programming languages keep making a comeback: people keep thinking they could make programming easy if they could just get rid of that pesky "code" part.

Really I think what the popularity of YAML is saying is that we need a vastly simpler programming language.

Most programming languages are written to impress other programmers. We need a programming language which is trivial to learn, which you couldn't ever use to write a webserver, but you would use it to configure one.