There are mean people everywhere, especially when they can be anonymous. I've been on the internet long enough to remember when corporations weren't the arbiters of what can and can't be said in games. Back when servers were owned by players.

The DHS has no responsibility to investigate what is most likely an edgy 14 year old saying edgy things in a game. The only thing that will come from this is, indeed people say mean things on the internet, therefore total censorship is the only answer. They will find a few real cases. Things like you pointed out. These will be use for a typical on-brand message about how widespread the phenomenon is. No one wants extremists in their country and all they will have to say is something like "first person shooters are a hot bed for white nationalists" and suddenly we are back to 1991 when we thought that first person shooters caused people to become violent killers. History repeating itself.

This is basically a solution looking for a problem. The particular flavor of radicalization "white nationalism" or whatever is being spammed in the media ahead of an election because it's the current party's boogeyman. It's scary, it sells ad space, and it drives campaign speeches. I'm inclined to believe that the population of these alleged "white nationalists" is a lot smaller. At least until they arbitrarily extend the definition.

I suspect the actual problem is rising inflation, lack of housing, lack of income to afford anything, and the 1000 mile wide chasm between the incomes of congress and the average citizen that are leading to the majority of radicalization. However, this will never be discussed because it implies the government is the problem. When the investigators investigate themselves they always find nothing wrong.