Using they when you aren't specifying is fine and any indication otherwise is just virtue signaling. If someone used they despite knowing I use he/him because they don't know me well, regardless of whether or not it's stated, it's not an insult.
You aren't much more virtuous for using someone's preferred gender just as you shouldn't be demonized for not knowing someone doesn't use "traditional" gender ideology.
Xbox had voice chat back in 2002. 23 years ago.