The same thing is true of the Jem'Hadar in Star Trek: Deep Space Nine. Clone race, no particular gender, all male actors and male pronouns. (Though I suppose they could all be actually male. But it does make you wonder.) Unlike the Vorta who are also cloned but have binary gender. Or the Founders who are shapeshifters whose natural form is a pile of honey-coloured goo. Whether or not they have innate gender of any kind is never outright stated, but the main one we get to know gets male pronouns and a male actor.

The default-male strikes again, eh. Sigh.