It is also telling that it is used exclusively to undercut progressive stances -- things like feminism, liberal immigration policies, fair pay, etc. It is never used to undermine the position of someone who who has made a typically conservative stance. Let me demonstrate.
Statement 1: "I wouldn't want to work there because they have a reputation as having a sexist work environment."
Rejoinder 1: "Your obvious virtue signaling is a joke. I don't care what you think."
Statement 2: "I believe in the constitution and believe guns are a significant foundation to the freedoms we enjoy."
Rejoinder 2: "You are just virtue signaling. Ooh, look at me, I'm such a patriot. Ha ha."
Why is it we only see type 1 rejoinders and not type 2?