I think the opinionated approach is what made json “win” the format battle more than anything else. If you’ve been around enterprise in the early 00’s you’ll know the horror that XML became when people weren’t using it in any sane manner. Which a lot of people simply weren’t, for whatever reason. Now this is anecdotal but over the decades I’ve never had issues parsing json, and I largely attribute its strictness to that. Yes I suppose you could abuse it, but I wouldn’t have to parse your nonsense, which couldn’t be said for XML.

I don’t have anything against XML by the way, it was purely horrible to work with because people were using it in so many weird ways. Personally I prefer toml, but I guess we all have our preferences.