Dragonborn were once a very spiritual people, created by the Old God Bahamut. Five hundred years of silence from their god, along with the need to survive in a changed world, contributed to their current secular worldview.
Lately, there have been rumours of groups worshipping the Dragon Gods of old—Io, Bahamut, and even Tiamat. Even more, these Dragonborn say that the gods respond to their prayers just like the new goddess of the Gatekeepers do.
Imagine how the world felt about the Jewish people after WWII. That’s how Alphai felt about the Dragonborn after their homeland was destroyed by Bael Turath. They went out of their way to help the remnants of this race, but Dragonborn pride refused to succor any aid. Most Dragonborn integrate themselves with whatever society they’re living in at the time, but keep their heritage and spirituality to themselves.