They updated the article to provide further context:
Later, in June 2025, the mod’s original uploader deleted it from Steam entirely. In other words, Valve did not remove the mod from Steam (as our original article suggested).
So Valve only restricted access in South Korea, not the rest of the world.
For such mods, there is pretty much always a very firm emphasis on “this is a work of fiction” when starting the game/mod. Example is the Assassin’s Creed games, where they don’t always have historic accuracy, but that’s okay because they have emphasized that this is a liberty they have taken, and they have already made the user aware of it and agreed to the terms.
This mod however (without having tried it myself) does not make any emphasis on this, and hence uncritically portrays it as part of real events.
They updated the article to provide further context:
So Valve only restricted access in South Korea, not the rest of the world.