The word “Master Race” is clearly equivalent to terms which were used by Nazis and so are today’s far right wing and alt-rights.
There are other communities which created similar narratives, especially from the 4chan side, and I think the origin of “PC Master Race” comes from there.
The name is actually poking fun at both the concept of believing in the existence of a master race and the users themselves. It’s not because the creators or users of the community actually think they’re the master race of OS preference.
Calm down.