Alice and Bob both go to a conference. Alice gives a great talk, and most people understood it. Bob gives a much more technical talk filled with jargon which almost everyone failed to understand. Do people walk out of the talk thinking Alice must've done something simple while Bob did something profound?
I get the feeling that this happens - after all given two concepts, one which I understand and the other which I don't, it's intuitive that the one I understand is the simpler one. It also feels like the easier-understood the talk is, the more questions Alice receives that aren't directly related to her work. For example I once attended a talk where the speaker talked about aggregating samples of the sky, and someone asked "why do you use square samples? Why not circles or triangles?". This kind of non-specialist question is obviously hard to see coming, and the you-either-know-it-or-you-don't result is uncomfortable.
On the other hand, if it's indeed true that giving easily-understood talks makes people think you did something simple, it would imply that giving comprehensible talks is a bad thing. That not only sounds silly, it's also counterproductive.