It's a part of the history. The original PCMR started back when the mods of the original /r/gaming banned posts about PCs, saying "There's nothing inherently gaming about PC. You could just be using it as a tax machine for all we know". This understandably created friction between the 2 cliques of gaming, with the console clique calling the PC clique a "master race" as a form of insult. At some point, everyone got fed up with arguing about it. /r/pcmasterrace was made, and leaned fully into the "master race" out of spite, and was spurred on by PC hardware at the time being way more cost effective than consoles. Over the years things mellowed out and it became less and less about console peasants "individuals who at the time insisted that console was superior, not individuals who later could only afford console after PC hardware went up in price. Important difference" and more about becoming one of the master race "owning your first gaming centric rig".

If you wanted the tried and true down to earth gaming forum equivalent for PC, you're looking for the PCGaming magazine. PCMR will always be an enthusiast forum, that was based separating themselves from the console ecosystem.