The correct answer to this open question is the following.
Unfortunately, you did not include the lecture, so we do not know what was the information included in the lecture. Just you know it.
However, trying to help you we did some deep research to find the video. So if you are talking about John Gerzema's video, then we can comment on the following.
What happened to "savings" in the United States, and how did consumers contribute to this change according to John Gerzema's video "The post-crisis consumer," produced by TED, is that consumer's savings dropped 10% and today the savings level is "cero."
Consumers have money during so many years that they exceed the purchase of the things needed and bought many things that they did not need, just for teh action of continuing to buy things. A hundred percent consumerism!
So after the crisis, consumers understood the way they excessively purchased in the past, and now, most of them do not have savings and are just buying necessary things.