Me thinks you have never looked at the field. I'd as soon declare csv is an error free format. Only true if you ignore the proliferation of applications that get it wrong. In subtle ways, often. Still wrong.
csv is wildly ambiguous, to the frustration of ~every data science engineer in industry
json is not
show me an application that parses `{'a':'b'}` as valid JSON, i'm actually interested, probably there are some which exist, but there is no ambiguity about those applications being wrong
Apologies for the, in retrospect, somewhat lazy posting of an article with no comment. I thought that article had a section about how many of them allow single quotes if you don't "enable strict." I am not seeing it on review, though; so either I made that up in my mind, or I'm remembering another article. Either way, apologies.
I did find https://github.com/json5/json5 no a quick search that basically says what I asserted about people just jumping to another standard for things that you hand write. I was probably also thinking heavily about python's dict syntax. (And I confess, I still don't know when to use single versus double quotes in python...)