I've never thought of "A Link to the Past" as meaning the game is prequel to the NES ones. I think that the title being a reference to the actual game's events made more sense. The entire game is about the events of an ancient legend passed down from long ago affecting the present time, because the legend was largely forgotten. Thus, the game events, in which Ganon is trying to escape his seal, are a "link", connecting "to the past", namely the past events of the Imprisoning War (or retroactively, Ocarina of Time). It seems like this interpretation describes the game itself better, as opposed to its not-entirely-certain timeline placement.