Why is "Gunpowder artillery in the Song dynasty" trending?

Wikipedia Overview

Gunpowder weapons in the Song dynasty included fire arrows, gunpowder lit flamethrowers, soft shell bombs, hard shell iron bombs, fire lances, and possibly early cannons known as "eruptors". The eruptors, such as the "multiple bullets magazine eruptors", consisting of a tube of bronze or cast iron that was filled with about 100 lead balls, and the "flying-cloud thunderclap eruptor", were early cast-iron proto-cannons that did not include single shots that occluded the barrel. The use of proto-cannon, and other gunpowder weapons, enabled the Song dynasty to ward off its generally militarily superior enemies—the Khitan led Liao, Tangut led Western Xia, and Jurchen led Jin—until its final collapse under the onslaught of the Mongol forces of Kublai Khan and his Yuan dynasty in the late 13th century.