I don't think this is exclusive of men, but anyway, if the reason is what I think it is, then I can see how it would be more a male thing, while I believe that actually, FEW people have a feel for subtelty and most in the world think they need to make it all like a pre-school class (check the movies of our time compared to those of decades ago, no abstract ideas, no unresolved issues, they make wuestions and provide the exact answers and you can even predict them, those sell because the masses like them, they have that kind of mind and is MOST people, hence they earn millions) but I think there's another more important reason.
we all want people to listen to us, to REALLY listen, and enage on what we are saying, but often times people don't listen, so we get used to thinking they are ignoring us, even if they are not, an example, you talk about a thing that is a passion to you, like for example, you are a musician, and give a speedy long speech about chords and how the instruments fit together, how it has X or Y influences, and the guy listen to you, with REAL attention and feels your passion, but understand almost nothing :P
when you pause, because it is a chat and he is expected to say something (or he has that impression), there's very little he can say, honest answer would be "I don't know any of it", but then you'll be like "ohhh (with the face of someone who told a really bad joke and realized nobody got it)" so in order to save you that feeling the normal answer, the one most uf us would say is "sounds great".
problem is, that, like saying "ohh I see" or "ohh ok", or just nodding, or mimmicking (if you smile he smiles, if you laugh he laugh even if he doesn't get it) are felt, even if that was not the intention, as someone who is not listening and just pretending to do it, and vague answers like that would upset many people, but specially girls, since male usually don't take it too hard if people just pretends to listen, but most of us would be carefull of even by mistake make a woman we care about feel like we are just pretending, we know better than that.
so be easy on them, that may be their way of saying "I know less than you or nothing at all, but just so you see that I listen to you I'll answer with the little I know of the topic you brought, and is not just for talking, is for you to see I DO care"