Agile will be dead as long as it's the dominant management methodology and there are page-views to be had. It'll be replaced with essentially the same process but with different terminology. Long before the Agile Manifesto, when I was working at NASA, we talked about the reality that the state of knowledge about a project is at its lowest at the beginning, and that any realistic project planning and management process must acknowledge and accommodate that fact. Subsequent research has confirmed that human beings consistently underestimate complex tasks, and that this bias persists even with experience, so no matter what methodology you adopt, you will always be under unrealistic deadlines. This results in distortions to whatever process you use, and flaws in whatever product you produce, and these distortions and flaws will be blamed on your development process, since no one will accept that it's simply an unfixable feature of human nature.