This article misunderstands what a "culture" is. Specific activities do not constitute a culture. Niche interests within a single domain do not constitute a culture. "Interest in Marvel movies" or some other figment of pop culture is not itself a culture, not by a long shot. This is why we can speak of a "pop culture" in the first place, because we sense that many things - nominally unrelated products situated within different domains though they may be - are all related in some important way, contained within a broader popular culture that transcends any of its manifestations. Perhaps the defining mark of popular culture is that the people who consume it and participate in it tend to overlap, or resemble one another. This way of thinking means that cultures are defined more by their participants than anything else.

Culture is broad, it is cohesive, and it extends and influences across many domains. There are absolutely countercultures out there, but most people aren't aware of them given how dominant the dominant culture is, which is generally the case but especially true today.