"Virtue signaling" is the all-purpose response to anything they don't wish to do solely because you wish them to do it. They don't have to engage with whether or not it's a good idea. They don't have to engage with whether you're being serious or not. It's just a two-word dismissal: if you care about it, it must be wrong, and no further thought is necessary.

For me, it has a convenient counter response: nobody using the term "virtue signaling" has anything useful to say, on any topic. It's "vice signaling", their call-out to their buddies that they, too, don't like anything you say solely because you say it. They're not listening to me, except for the purpose of rejecting it reflexively, so there's no point in talking to them.