Had “Antifa” in my username and they gave me a 7 day ban, for glorifying violence. Its crazy how much hate I would get on account of my username in multiplayer games but I never really cared, nor am I that upset over a suspension but I was usually under the auspices that usually platforms warn you about names not a strict suspension
I’ve only heard it used in the context I’ve used it.
It can also mean an omen, which might be how you’ve seen it, but still doesn’t really fit here.