I think "plain text" in most cases really just means that it can be read and written by a human in a basic text editor. It is not mutually exclusive because par

I think "plain text" in most cases really just means that it can be read and written by a human in a basic text editor. It is not mutually exclusive because parsers can be written to handle more freeform text than just csv and markdown. "Plain text" is like a carrier wave that can hold a format like CSV or markdown, or loosely conventioned prose that the right kind of parser can make reasonable guesses about. Your semi structured blob format and mine are still plain text. They are comprised of the basic set of characters from 32 to 126 maybe and 13 and 10, and maybe multi byte things these days. Plain text just ain't what it used to be anymore! They may not be standard formats, but they can be read and learned about in standard tools. But your cautions still ring true, as I have created several such formats and have yet to hit on something that is easy to write, and somewhat easy to process, and ticks all the other boxes. Good luck with your upgrade!