Are we doomed?

In her book
Dark Age Ahead, the late Jane Jacobs argues, persuasively, that western culture is headed for a new dark age, and that in this dark age the knowledge and expertise we now possess will be lost. She points to Dark Age Europe, where societies that once thrived suddenly collapsed, the people of those societies forgetting how to maintain the bedrock of their cultures: agriculture, irrigation, education, so forth.
How is such a thing possible? How does a society forget how to plant and care for crops? Well, here's one way: there is a shift at the top of the society's power structure, wars are started for the benefit of the ruling class, the society's economic framework is re-purposed to serve the needs of the power-mad, ignoring the needs and interests of the lower classes, there is a societal shift where the caretakers and practitioners of vital knowledge are driven away, or isolated, or killed as knowledge itself is demonized. And inside of a generation, superstition and ignorance become the norm. Suddenly, the center cannot hold and the society collapses, generally overthrown by the next rising power.
(That's the one thing
Idiocracy left out -- the fact that, once the US gets as stupid as it is in the movie, they will have been long-before taken over by, say, China.)