This is a dumb article that doesn't actually explain what it's describing. The only difference between the Internet now and before is that there's more of it. There has always been a separation between people who use it and know the memes and people who don't, and there have always been infinite subdivisions between the people who are on it but who aren't on the same sites. Younger people have a higher proportion of their population who are on the Internet, and therefore also have more subgroups coming up with more in jokes, meanwhile the older you are the more likely you might have lost interest in the Internet all together and stopped interacting with it at that level.