Not always true, I think they do it for both, I have seen adults arm wave to be dominant, and hatchies too, how? Because if they dont get the arm wave message they get chased away with a few seconds! Petes are a classic for this! My juvie Easterns arm wave to be dominant and my Adult Vitties do it too.
I have noticed though that generally the females are always waving, the males kinda just chill or go crazy head bobbing ask alexr about his male when he saw his new girlfriend! hehe