That's certainly a problem, in that many students are over-anxious about critical quotes and hence over-use them. But it's really a separate problem, overlaid on the far more profound problem that they really have no idea how to select and arrange the quotes they use in order to make sense, let alone construct an argument. I've noticed this over, ooh, about thirteen years of teaching now: across the years there has been a significant decline not in intelligence or insight, but in the ability to express them.

The article to which I linked follows up on Greenfield's idea of construction by connection by commenting, "The flickering up and flashing away again of multimedia images do not allow those connections, and therefore the context, to build up. Instant yuk or wow factors take over." If there's a single factor I've noticed in student essays over time, it's fragmentation.