In the new Aquaman movie there are a number of scenes where Atlanteans are seen on land wearing suits filled with water so they can breathe. In some of the fight sequences we even seen their suits breaking and the person inside "drowns" like a fish out of water.
Yet Aquaman, his mother, and numerous other Atlanteans have no trouble breathing both air and water. I suppose in Aquaman's case he was half Atlantean and half human, but that doesn't explain the others who had this ability.
I felt like this was either not explained at all or else I missed it. Why do only some Atlanteans need water breathing suits while others don't?