Side question, but does anyone know why specifically 2^-32 is the target floor for attacker success (in footnote 3)? I found another mention of the 2^-32 target

Side question, but does anyone know why specifically 2^-32 is the target floor for attacker success (in footnote 3)? I found another mention of the 2^-32 target in [0], but I'm not even certain they're related. [0] https://csrc.nist.gov/csrc/media/Events/2023/third-workshop-on-block-cipher-modes-of-operation/documents/accepted-papers/Practical%20Challenges%20with%20AES-GCM.pdf https://csrc.nist.gov/csrc/media/Events/2023/third-workshop-...