I understand where the author is coming from and respect their contributions to Commonmark. But... There are tons of markup languages for prose that have well-defined specs. So, why did Markdown win? IMO, because it does not have a well-defined spec. It is highly tolerant of formatting errors, inconsistencies, etc. If an author makes a mistake when writing Markdown, you can always look at it in plain text. Whereas a…
But in the case of MarkDown the original implementation was just not that great. Which has nothing to do with being easier; MacFarlane’s Djot is an easier to implement and easier to describe language.
And of course your point about “committee-driven pursuit of precision” is just a made up hypoethical which is not worth responding to. (The only committee has been on CommonMark, which is a definition of “MarkDown” (TM) which merely tries to deal with years of drift between different MarkDown implementations. With their famously long-winded spec-by-prose-enumeration style.)