"IT" security covers cryptography that has been standardized enough to be used in the IT industry. CS Theory should only cover theoretic cryptography, the likes of what is covered in the TCC CFP. Crypto will cover the majority of the remaining crypto research that is not theoretic/foundational and not standardized/deployed.

That is fine if you see stack exchange as just a list of questions. I liken it to a community: users build their corner of SE, gain reputation, chat with other users in their area, etc. I think these aspects are influential in attracting and engaging the top researchers in a given field as much as the questions themselves. It doesn't work quite the same when you are split between four sites. Anyways, it is decided now.

PS This is only to argue that the proposal should not be closed. I agree the scope of the proposal is be revisited (and made as wide as possible).

I am happy to see Stack Exchange mirror conferences. Yes you can send your theoretic crypto papers to STOC/FOCS/TCC, your applied crypto papers to Oakland/CCS/Usenix Security, and your implementation papers off to FSE/CHES. That does not preclude having Crypto/Eurocrypt/PKC/FC/RSA-CT/etc/etc.