[AnimalMuppet]

At least in the political realm, memes have worked for a very long time - at least more than a century, maybe even millennia. An example: "Ma, ma, where's my pa? Gone to the White House. Ha ha ha." Another: "Peace. Bread. Land."

So I would say that there seems to have always been a segment of the population on whom political memes were effective - probably more effective than longer discourse.

Now, you could argue that more people are in that camp today. I can't argue with that; I don't have any data one way or the other. But I would at least suggest the alternate possibility that it's more visible today that people are in that camp.