90% of when I use JSON is when I control both sides of the interaction. E.g. a web app where I have no expectation of third party clients, or a config file that

90% of when I use JSON is when I control both sides of the interaction. E.g. a web app where I have no expectation of third party clients, or a config file that will only reasonably be read by one program. JSON is normally "good enough" as a general wire interchange format, and it's human-readable and whoever comes after me will already be familiar with it. But if there's a time when it's not good enough and its failures are in expressiveness, I'd totally consider JSON5 or some other alternative instead.