diarrhea writing disorder
One that suffers from feeling their writing is eminently significant, produces it in voluminous quantities and in unremarkable (often unsolicited) contexts to such an extent that reading it can result in toxicity for passive observers.
"I think I am going to be sick from reading the diarrhea writing disorder afflicted emails he keeps sending on the same topic that are nine paragraphs long with three-four sentences each."