When using AI, I often find myself preferring either plain text (no markup whatsoever; just manual / text editor formatting of text blocks) or simple html to markdown, depending on the situation. To the point that I rarely see any point in using markdown for anything. If it is meant for to be a simple text mainly for human consumption, the markups often don't add much clarity (and often bring in an amateurish look, as if the author didn't know how to emphasize using English constructs), in which case plain text feels more pprofessional. If it is meant to be [lightly] processed before being presented to a human, or if it is meant to be processed by a tool / bot / LLM, then HTML is infinitely more straightforward.

Also I often call out my colleagues if they try to put a table in markdown. Markdown is not built for tabular data in most professional settings (i.e., one or two table cell could easily take a whole line of markdown to express). A basic <table><tr><td style="background: red">some number</td></tr></table> goes a long way.