You generalize from one case. Also you don't know what you're talking about. Lots of big writers use markdown editors.
You generalize from zero cases, so I'm pretty sure I know what I'm talking about better than you do given that I have at least a single case.
And no, I didn't generalize anything. I said what my mother does. You inferred that I somehow meant that all authors do exactly as my mom does. I went on to state what the purpose of word processors and text editors were, then said I wasn't sure what a markdown editor was for.
Thinking about it, maybe they're nice for writing online posts/articles? Those aren't really meant to be printed out, but often have various inline formatting like markdown offers.