I mean the discrimination in this universe seems to be really bad. This is why Haruka’s mom is always trying to prove herself as an alpha because society said so, and since she is also a woman, she needs to prove herself even more. She thought Haruka wouldn’t survive because he is weak. Kosuke is an omega but their parents denied his nature and personality. Since they didn’t understand and don’t know how to treat him, it caused him pain for a long time. It seems like they are raising him as a beta male instead. That is what they want Kosuke to be. The old man literally called omega as crazies because that is what omega was perceived back then. Forget same-sex couples! It is all about survival at this point.
Why are there no more same-sex couples? Outside of the main characters and the alpha's mom, everyone else seems to be in hetero relationships. That's not bad, but considering it's an omegaverse, there'd be more variety.