This is completely normal psychology.

However, once you rule out the actual aware psychological exposure to the material and the effect that has on normalizing things, things get more interesting.

However, none of the "dissemination and normalization of ideas, concepts and mental models" requires a simulation, or a hive mind.

Something X that connects all those who think/conceptualize/mentalize.

In oldest known spiritual texts this is the all-encompassing unity oneness that we all tap into. Some call it brahman, some Tao (no, "tao" is not "the way" that's a misnomer by idiots who should know better), some godhead, some something else.

Yes, if you want to stretch it, you can force your own model like "simulation" or "hive mind" onto that model, but the problem is that the forcing actually breaks the model itself.

The phenomenon described in the 4chan post is not new and hundreds of thinkers have come across that throughout the ages and written publicly about it.