From Age to Age, from Revolution to Revolution, specialization has increased.
Hunter-gatherers were mainly specialized between men (hunters) and women (gatherers and children-raisers)
In the Agricultural Age, priests, soldiers and specialist artisans were the specialists that did not produce their food.
In the Industrial Age, a multitude of specialist trades developed that did not produce their food and only contributed a small part of the production process.
Specialization cannot develop without trade. Specialists spend their time on their specialty and cannot get what they need to live without trade. Specialists need trade to develop to exchange their production and get what they don’t produce.
Beyond the Fourth Revolution, specialization will further increase. Even maybe to the point where each individual will be recognized as an individual specialist in it’s own self. In any case trade will also necessarily further increase.