All right, maybe you do have a common tool that implements a query language so that you can filter out certain paths and objects from the JSON data into a thinner data set with known formatting expected by the next command in the pipeline. Then you need to write that command and you need more instructions, possibly again in another language, to describe what you actually want to do with the data now that you know where to find it.

At this point you typically write a separate script file to do this because it's easier to express in full-blown programming language what you want to do with the tree of hashes and lists and values. On the other hand, programs for lines of text are quite short and fit on the command line.

I don't see an immediate value in structured data, and especially none that would outweight loss in general applicability and usability in comparison to text based data processing.

Don't get me wrong: I would love to see a good prototype or sketch of how such a thing would work, and then try to imagine how I might be able to apply it to similar things for which I use Unix command line today. But I'm sceptical of "how" and also quite sceptical of "why".