Earlier quoted context omitted.
To "ghost" someone is to avoid them without a response. The term probably came from personal relationships (e.g., a woman you were dating starts "ghosting" you). It was previously considered rude but is now appropriate to avoid potentially toxic personal or professional relationships.
Pretty sure it's still considered rude.
I had this one English teacher who squashed any interest in writing after I took his class. He was known as Red because that's what color our papers were when he was finished grading them.
He did say a few thing that felt right. One was just don't use cliches. The other was don't use slang.