Do humans fail to cite sources in casual chats? Probably.
But our human colleagues in #academia deviate from the #AI case above in a few ways:
(1) My human peers often admit when they don't remember a source, "I don't recall the citation, but I was recently reading a study which found that...."
(2) When #writing, my human colleagues and I fight like hell to track down citations for every claim. We search online, ask colleagues on #socialMedia, etc.
(3) If we can't find the citation, we revise: the claim becomes a hypothesis, the claim is abandoned, etc.
I don't see #AI do 1-3. It should.