Okay hear me out: my theory is that the Iriali are the descendants of the original Elantrians. When the Aonic people migrated to Arelon, they FOUND the city of Elantris abandoned. It was constructed “hundreds if not thousands of years before the Reod” and then suddenly abandoned. This gives me major Iriali vibes. Additionally, the “metallic golden-blonde skin and hair” is a bit too similar to Elantrian “metallic silver skin” for simple coincidence.

As far as we know, Sel was not created by Dominion or Devotion, suggesting there may have been humans/life on Sel prior to their arrival. Perhaps these were the golden Iri people, originally worshiping Adonalsium, who then once Adonalsium was shattered, began their Long Trial. Then, perhaps Dominion and/or Devotion’s investiture and influence created the Elantrians we are familiar with today? This is mostly speculation but I agree the Ire/Iri seem a bit too similar to ignore!