You're choosing to focus on minutia instead of the point of the statement: no SE site embraces theoretical networking questions. Regarding your comment about networking is off-topic for SO, that's technically wrong. Theoretical networking questions are part of Computer Science, which Jeff endorses for SO participation

FYI, the biggest problem with status quo (before the beta site proposal) is that theoretical networking questions fall through the cracks of both SO and SF... neither community truly embraces them, although sometimes you can sneak one through on SO (and Jeff officially said they are welcome there... different story for close-voters who love to hammer anything pure networking on SO)... disclaimer: I have not even signed up for the beta, but I am a professional network engineer and I've been somewhat frustrated by options for supporting my profession on SE to date