I think he was just saying that you identify so much behavior as signaling, that pointing out a given behavior as signaling is redundant. Specifying what the behavior might signal (among other things) would be neither inane nor tautological; it’s just that in the context of the overwhelming signaling you hold to be all over the place, saying “Activity X is done for signaling purposes, perhaps subconsciously so” is like saying “that cubic foot of apparently empty space is occupied by air, and some amount of water vapor the exact amount of which varies with overall humidity”. Sure, it’s true, but there is no obvious reason to say it about that cubic foot of apparently empty space and not all apparently empty space near Earth as a whole.
I think he was just saying that you identify so much behavior as signaling, that pointing out a given behavior as signaling is redundant. Specifying what the behavior might signal (among other things) would be neither inane nor tautological; it’s just that in the context of the overwhelming signaling you hold to be all over the place, saying “Activity X is done for signaling purposes, perhaps subconsciously so” is like saying “that cubic foot of apparently empty space is occupied by air, and some amount of water vapor the exact amount of which varies with overall humidity”. Sure, it’s true, but there is no obvious reason to say it about that cubic foot of apparently empty space and not all apparently empty space near Earth as a whole.