“It’s an insult in their minds”, said a commenter above. Being that you speak flawless Yoruba, I’m surprised you didn’t reach the same conclusion. You know Yoruba is littered with ‘omo ___’ for every kind of human lol. ‘Omo Yooba’, ‘Omo onile’, ‘Omo Hausa’, ‘Omo ita’, ‘Omo Ibo’, ‘Omolomo’, ‘Omo Oyinbo’, ‘Omo oku orun’ (lol), ‘Omo London’, ‘Omo Ondo ni mi’ etc. etc.
In my experience, it’s that someone is trying to belittle you by reference to where you come from. Simple. But it’s also an innocent way to describe you, the referent. Context helps me pick. So in confrontation, it’s always going to be the former. I’ll be the first to admit being tired of the way Yoruba people casually belittle other ethnicities in our midst. Our towns and cities tend to host many ‘foreigners’ so we’re largely uncurious about the differences b/w people groups. I’ve yet to live outside the SW, so there remains much for me to learn in getting the whole Nigerian picture.
But it seems like this may just be the backside of the ‘Omoluabi’ concept. I can be born and raised in Lagos for 70yrs, but I’m still considered an Omo Osun at root. And I think that partly explains how the Yoruba avoid ripping each other along sectarian lines. That Muslim boy may share my religion, but he’s also Awori — and as we are in Odo Oba, I will not slash other Iwo sons and daughters b/c they are Christian, and some Imam (allegedly) called for revenge. The same thing that relativizes religious sectarianism, ISTM, emphasizes the ‘foreign’ status of non-Yoruba people in Yoruba lands. My thoughts aren’t fully formed on this, but it came to mind the last time I read someone talk about ‘omo ibo’ being used on them as an epithet (and he also isn’t Igbo lol). I think that better understanding this dynamic in the SW could go a long way in teasing out why the ‘state of origin’ and other strange concepts came about in the first place, and what good they were meant to secure (narrow-minded or not) esp at the seat of power: Lagos. You can probably tell already that I don’t think it is completely nefarious, but I can admit that many of its fruits are horrible — and may even holding us back. It’d be worth it to understand better. If only we had (funded!) sociologists.
As per the simple wickedness of man, epithets are not a puzzling thing to explain. And they are certainly not the sole province of the Yariba, those quarrelsome Omo Oodua lol.