Some guy wrote a book about this but basically it's hunters (in the Hunter-Gatherer sense) stuck in a farmers world.

SO back when humans primarily hunted and were nomadic, prior to the advent of agriculture and sedentary farming (where seasonal planning and forecasting was required), a lot of required traits for survival: high-vigilance, impulsivity, and novel-seeking - were what made great hunters and survivalists.

People with ADHD just have the wrong OS for this era or more like they are peak human (Windows XP) and current humans are bloated Windows 11... it's evolutionary enshittification.