Recently I overheard that our company intends to use markdown for configuration purposes - replacing yaml and stuff. I am not against the idea but it did surprise me because while I am happy with writing documents in MD, it never occurred to me that it could be used for configs. Not sure what the upsides and downsides are.
Sounds like literate programming. I've used it once or twice for training material and as "fancy" slides at an internal presentation. Worked quite well as one-offs but I'm not sure that scales wrt its usability and maintenance.
Things like jupyter notebooks and observablehq.com seem to be bringing in a breath of fresh air to literate programming.