The author does not say "work in a text editor", only "use". Considering she's including text editors on mobile devices, which the majority of America will utilize today, that's not a particularly bold statement.
I suppose when I send a text I am using a text editor of sorts
Disagree. Paragraph context and examples made it clear she is discussing a dedicated text editor, not something embedded in e.g. your SMS app.
Can't imagine why parent is getting downvotes - it's an important point, and doesn't seek to invalidate the whole piece.