Arnold Kling, 64, an American economist and Israeli folk dancer since his student days at the Massachusetts Institute of Technology (MIT), has another theory. Kling, of Silver Spring, Maryland, contends that the nature of engagement in general has changed in 50 years, becoming both narrower and deeper. Increasingly complex new dances discourage beginners from trying Israeli folk dancing. Veteran dancers come for the “oldies,” those choreographed before 1990. That leaves a large generation gap of people who can’t relate to either end of the Israeli dance spectrum — thus the decline.

UPDATE: here is the link

The paragraph is a bit terse–a condensed version of Narrower, Deeper, Older.

I’ve attended some of the sessions pictured in the article, but I have managed to avoid being in the pictures. The second picture shows a session I attend regularly, but I think it was taken when I was out for a couple of months with a foot injury. The picture was taken early in the evening, when there are a lot of new beginners and perpetual beginners. There are three women dancing facing the camera, one with silver hair and two with arms high over their heads. I am confident that they know what they are doing. The rest of the dancers are. . .trying their best.