The internet loves to hate it. Untyped, whitespace sensitive, need quotes for random strings, ...
I think it's passable, just wish it was a bit less "powerful" in special strings.
My editor yells at me when it autocompletes and inserts tabs :facepalm:
&anchor node and
*anchor to reuse things may be powerful but sure looks confusing)
(type tags look horrible)
Too unspecified / no standard
Ugly keys, no comments
Okay for key value pairs (ini like) but has weird array of objects syntax, needs repeating the array name, and doesn't have a good looking way of indenting nested heirarchies.
You hate humanity.
These are more like programming languages, powerful, but harder to see the result without evaluating it. For some the output might change depending on the environment.