In regards to the oppression, I have a simple argument that I use personally; gay people have gotten beat in the streets, and trans women shot to death in my community. Ace people do not face oppression that stands as similar; they are marginalized themselves, but they do not face the same struggle queer people have and do face. I keep bringing up the pink triangle, Stonewall, AIDS, the modern day nations where it's illegal, and the nations where it's legal but you run the risk of getting killed if you go out in public. As far as I'm aware, there are no systematic oppression of comparable scale for being ace alone.

There's no need to strain queer spaces and resources by opening them up to any group that's marginalized; like I said, I'd prefer the idea of having an overarching label including aces, but I don't think cishet aces should be considered queer by any means.