Do questions on whether a hash function is almost universal belong here or on math.SE? They seem to belong both places: on math.SE because the question is about mathematics, and here because cryptography is one of the main uses of such functions.
Mathematics applied to cryptography is on-topic here. If the question is good, but the connection to crypto is too weak, we'll migrate it to math.se.
The only doubt I have about your question is that it might require in-depth cryptoanalysis of the primitive you're asking about, in which case it wouldn't be acceptable here. If the answer can idealize the primitive, e.g. to a PRF or random permutation, it's likely on-topic, if it requires differential cryptoanalysis it's likely off-topic.