Maybe some people are too quick with the term, there always will be people like that for any label. But just consider all the people just as tired of real conversation being shackled by "virtue signaling" as you are of being called a virtue signaler.
Also, you could write your disgruntled comments about any label. We are certainly way too quick to find racism where there isn't any. Yet there are also real racists out there complaining that the charge of racism is really getting on their nerves. Does that mean we stop charging people with racism when we see it? No, we're trying to call out unacceptable behavior.
If we're getting into pet peeves, mine is "gaslighting". Everything is "gaslighting" now. Accidentally spread a small inaccuracy? Gaslighting. Tell a public lie? You're now "gaslighting the world". Sharing my disagreement with you, like this comment? I'm gaslighting you.
If I say "don't be racist" and you call me a virtue signaller, you are implying that I don't actually care if you're racist, I just want social points for being "good". The problem is you don't know if I care or not. I might care deeply. I might dedicate my life to being anti-racist, but you can just label it virtue signalling and move on? that's an intellectually dishonest maneuver.
It can be incomparably frustrating as it focuses on non-issues or minor issues and misses the bigger picture. I personally don't see it used outside of those contexts but it shouldn't be used to dismiss actual action like doing your part against climate change.
Buying CFL lightbulbs is performative climate action.
Buying CFL lightbulbs is virtue signalling climate action.
One of them is about the action - buying bulbs isn't effective, the other is about the person - if you buy bulbs you are fake. Perhaps "performative" fails at making this distinction clear enough, but I'd like a way to imply that someone is all-talk-no-action, without undermining their actual belief in something.
ALWAYS dismissive and reductive. ALWAYS. It's not a good faith argument. If you think someone is all-talk-no-action, accuse them of being performative. If you think someone's cause is dumb, attack that. You can call ANYBODY advocating for a viewpoint a virtue signaller so it is an entirely meaningless attack.