In no small part because an idle gentry without prospects for meaning or avocation was the ultimate cause of the Crusades.
As to the quote, I've never met this "everyone." I've seen troubling signs that "employment" is about to suck even harder but that's a different thing. Both the Chinese and the Ottomans rejected automation and mechanization because they had enough idle serfs that employment mattered more than efficiency.
Believe it or not, there's a middle ground between an autonomous Uber and a palanquin. History is the task of finding it.