Honestly it didn’t but how can they be a couple without anyone being homophobic if the uke’s not popping babies out of his asshole?? Lol.
We don't even know if they will have kids and that's 900+ chapters from now on, so far they both seem against it. We also don't know if the ml can actually have kids since he was impotent before he awakened. Iirc no one who was awakened has successfully gotten a child yet and everyone is defo homophobic in their world. But you're right in the the way that they are (the mc's) thinking of using the ABO system to legalise marriage between both genders, and then further make it easy for everyone else, there's definitely opposition though. Ik the ABO is off putting (was for me) and I personally think the author has weaved it in perfectly into this story and its world building, it serves a role.
i am enjoying this so far but did it seriously need to be abo lmao