I agree I also thought the same at first: like, that straight omegaverse sounds painfully redundant. But then I realized t's not just the pregnancy thing: since Omegaverse does establish a power difference between the genders, where one gender stands above the other, and with their respective "natural instinct" helping to enforce that power difference (since it forces omegas to submit while in heat, whereas alphas are forced to subjugate), the role of "natural instinct" in omegaverse reminds me of how some animal species ALSO use "natural instinct" establish a sort of "hierarchy" between the genders: like bees and ants, for example (male bees and male ants serve only for reproduction, and female bees even "evict" male bees from the hive, abandoning them to their death, when they want to save hive resources!)
People who's against story with straight omegaverse are so funny, they must have develop a kink that omegaverse should only be for bl. For someone who read on illegal site too yall are choosy as hell