Right, they're are both too drunk to consent. But in a real life guy/girl scenario it might be considered that he raped her. But in reality they both raped each other.
Neither raped the other. They certainly didn't "rape each other." That's just stupid. If you think that's even possible, I'd suggest you have stretched the definition of rape too far. Thought experiment: try telling that to a real rape victim. Good grief.
What it does mean is that if one person accuses the other of rape, the accused can't claim that the accuser consented. But that still doesn't automatically make the accused guilty of rape. (And it would certainly be interesting if the accused turned the tables and claimed the accuser committed rape because the accused likewise did not consent).
To avoid this potential legal absurdity, some states have clarified that having sex with someone who is too drunk to give consent is only rape if the accused understood that the the other person is incapacitated. That means neither side is guilty of rape if they were both truly drunk - it's just two drunk people having sex. Which happens all the damned time.