Many researchers argue that mind-blanking is a common mental state, albeit tricky to measure. Attention is one of many thinking or neurocognitive abilities. Examples of other skills include concentration, memory, problem-solving, and mental control. Mind blanking is associated with specific brain regions (Broca's area, hippocampus, anterior cingulate cortex; 2).
In other words, mind blanking is a normal neurocognitive phenomenon.