That JSON has a "good reason" for disallowing comments is an opinion, it could be a popular, well-known and established opinion or it could be completely uninformed. To know the difference one must explain it.

Also standards change, and professionals use their tools in ways the original creators did not imagine a lot, that doesn't make them clueless. Heck, even JSON is a result of professionals misusing a programming language syntax for a serialization protocol.