JSON has its issues, but modern languages including facilities to work with it (fewer dependencies to wrangle is always great) and the way typesafe (de)serializers can be synthesized automatically with a little thoughtfulness in design instead of needing to be manually written (see Swift’s Codable and Kotlin/Java’s Moshi, for example) can in my opinion make it compelling enough to overlook its warts. It doesn’t fit everywhere of course but it’s more than good enough for a vast range of applications.