If that's what I were worried about then I think I'd just leave it at, "we didn't feel like our personalities meshed well" or "we don't think you are a culture fit" and leave it at that.
They could also be signs of a defensive response on the part of the interviewee, who may be nervous. It is also a typical response of any person trying to maintain their sense of personal space.
"Aggressive micro-expressions" sounds aggressively silly.