Not giving the dragon race the elemental class has to 10000% be an oversight.
Storm, earth, fire and water…
These are literal dragon tropes on top of the fact the lore reason of the other class is that they always existed but the primary goal of the Dracthyr was to combat the elemental Primalist why would they not learn shamanism in a way to combat directly the elements the Primalist use or use their abilities of shamanism to subjugate the Primalist forces.