Kandi Wiens:

However it manifests, it’s important to remember that workplace cynicism isn’t due to some sort of character flaw or being a “glass-half-empty” person. It originates from the workplace environment, not the individual. Many experts, in fact, see workplace cynicism and depersonalization as a form of defensive coping: Becoming distant and withdrawn is a self-protective measure that places a buffer between an employee and the emotional exhaustion and energy depletion their job is causing. Even relentless optimists’ protective measures can be broken down when they’re exposed to high degrees of stress, especially when that stress continues unabated.

I hadn’t made the connection between rising cynicism and burnout before.