But why JSON and not CSV [1]? Most of what the article suggests, like formatting the output as lines and flattening, is how CSV works. CSV is much easier to parse than JSON (use split(",") or the equivalent). A complete record (JSON object) of CSV data can be parsed in a single line, unlike typical JSON. The line-based nature of CSV makes it far more fault tolerant to broken streams/truncation and more in-line with standard Unix conventions.
[1] https://en.wikipedia.org/wiki/Comma-separated_values