[ktpsns]

This question is really not specific.

In scientific and high performance computing, people are regularly inventing new file formats. Many of these decisions also follow paradigms such as "We don't like XML nor complexity, so let's do as if it was 1980 and serialise these data as ASCII one datum per line".

Don't forget that your viewpoint comes from your community. If you are a CAD person, you probably never use JSON. If you do data research, you probably never use XML. If you do hardware development, you probably open any file with a hex editor anyway just because data is usually some bitstream for you.