You are right, but there has been a kind of "movement" in the sense that a community (Agile evangelists) tried to persuade executives that "Agile thinking" was a solution to certain problems (e.g. corporate slowness). Over time, those executives took more interest, and tried a lot of what was advocated by the Agile evangelists and the sales people of consulting companies. But we are in a time now when executives are losing interest instead of gaining interest. That is what I mean when I say that the movement is in decline. The ideas themselves are the ideas; ideas don't die - they drift into relative obscurity, but are still there.