I think the thing the author is missing is that there has never been one big culture. For a long time, the culture was segmented primarily by location: people in a region played the same sports and games, talked similarly, made the same music, and so on. Now, the culture is starting to split based on interests rather than geography.

It may be problematic that culture is now being sliced on this new axis, but don't just compare it to some imaginary wonderful past that never actually existed.