Not sure what to think on this one. As SEnkey points out, there are some implications to consider for the societal mores. But if someone is making a point for the sake of the moral issue, what's the problem?
Well worth the read. Many things can be true at the same time. It may be true that many people dismiss the sincere actions or voices of others as 'virtue signalling'. It may also be true that many people are not as virtuous as their words (are any of us?). So I like the conclusion, virtue signalling has its place, we shouldn't completely dismiss it one way or the other.
As a brief aside, my pet peeve is what others have called 'bravery on the cheap'. For instance when a college students says they would die to defend free speech, which is so easy to say in a safe environment. Of course, they could enlist in the military and fight or die for the ideal of free speech. They could attend marches and speeches of people with whom they disagree and face the counter protesters with whom they agree but explain why these other people deserve free speech - but they don't.
Is that virtue signalling? Not sure. On the one hand they certainly want me to know that they support free speech. But they don't often do much to actually, you know, support free speech.