It took me a long time to understand that the term "virtue signaling" has some value (although I still think it's too tainted for use), because I had mostly seen accusations of "virtue signaling" lobbed by alt right assholes at anyone who has principles.
But I have come to realize that a lot of liberal folks are very, very into virtue signaling. It's all they do. They don't think of the opinions they espouse as morally important. They are COSTUMES for some people.