Think about it
Why would the Great Beings assign gender to a groups/'races' of subserviant, sentient(after Velika came) robots with no... well nearly no biological differences what-so-ever? Imprinting on their creations? A tribute to themselves and the Bara Magna inhabitants? Personality-related powers and abilities? Some other motives? Discuss freely and don't involve controversial things into this
EDIT: I guess this could extend into gender-locking and other things, but we're talking about all the sentient races