Excellence of writing certainly adds to my enjoyment of heroic fantasy, but I've been known to get by on some pretty feeble stuff as well. The point is that the emotions is where the reader responds, whether at a high or low intellectual level. We might be looking for something other than to be dazzled by an author's mastery of, or cleverness with, the English language a la James Joyce. For this reason the works of Robert E. Howard, as simply executed as a naive painting, lacking technical excellence, resounds inside the reader with the author's emotional integrity, touching our emotions with his. We're all looking for something of our own spirit in what we read.
Fiction is a mirror.
If what shines back isn't very attractive, well, that was worth finding out. It was even entertaining. The point is that some of us have good taste and like heroic fantasy. That's less a conflict than may at first sound likely. It only means that for many of us, there is something special about heroic fantasy.