The argument you provided is based on assumption with no evidence to back it up. It's an argument made in extremely bad faith as it causes further derailment, worse faith when all of a sudden you pull the safe space argument out.
But let's turn the assumption part into a positive for a positive on topic point. From reading this thread I've seen multiple assumptions that are baseless or a woefully incorrect, dangerous and broad strokes as well. One of those is that the only people who are doing this and defending this are white, I can only point to the report that started this all off and just say that from reading that I know a couple of the people there are not white and have come up in the report and this thread to voice their opinion. If anything it sounds like the people throwing around the accusation that these people are white are simply deluding themselves and seeing only what they want to see.
The second one is that people who play these characters are fulfilling some sort of power fantasy. Last I checked I've not seen people dress up as Black supremacists and shoot up a briefing of white people nor have I seen Indians bomb Pakistanis in their prep room. In fact everyone plays their character role when it truly matters and the RP factor is left at that, RP. This assumption simply assumes that people will express themselves in a way that is intentionally detrimental to game play if they have freedom to do so. Let's expand on that further, you create a character, you experience a game in the role of the guy you just created and get insulted. Who is insulted, you or the character? To find that out one has to observe the interactions through the whole game. If the interactions late in game are with a white medic healing a chinese marine yet during prep they were arguing, one can say it was in character and good taste between the two of them. If they die and the players are arguing you can say there was genuine discontent between the players. But in that example I have not mentioned what they are arguing about or what was the insult was and who insulted who. You take things in principals and you can find a very easy way to deem what is going on.
Third assumption is that everyone is involved and has to be OK with something otherwise no one can do it. The reality at the end of the day is that if you personally are not involved with two marines having a go at each other then you're not really involved with the RP at hand nor are you personally being insulted. One could argue stereotypes, but generally ANYONE can perform them or fall into a category. If one was to get involved however you could personally RP a solution out as you wish. A Black guy can play as an Italian commander while a white guy can play as your stereotypical pavement ape, the two will interact if they wish and something will happen. If a problem occurs the rules cover this with a simple Ahelp and the one who is RPing as the offending party will be told to calm down but if you're the third party why should someone accept your report if the other two players actually don't mind. At that point you would be getting offended on another person's behalf. That sort of behavior is something people call virtue signaling which comes across as an attention grab for the sake of feel good points, needless to say it's not very popular to the wider community regardless if it's CM or another community.
The fourth assumption is that people take their personal real life grievances and views into a game. If you believe that's everyone and people are playing with their personal opinions on their sleeve, then you're delusional. People play games normally to escape reality, not further it in a fantasy. For those that do this they end up getting punished quickly and normally for a plethora of reasons as well like shooting up cargo or other such things.
The fifth one is that if this ends with no rule changes, it means the server is encouraging it. It's not.
I'd point out that, that's an incredibly lazy way to solve any issue and actually solves little to nothing at all. Worst part as well is your example of goon, how many people play Goon nowadays? It used to be rather high flying but now Goon is seen as something people don't bother with. Some cite rules, other cite the community and admins etc. The knock on effect could lead to chilling effects and sterilization of the server and some of the current character roster would be hit hard all for the sake of people not being able to distinguish reality from fiction. Also promote? I don't think a single thing would actually change much if the rules didn't change, you'd maybe see a small victory dance by those who see this as a good thing and pushing the envelop a little but even that is me making assumptions much like yourself is with that statement.