As a series, The Legend of Zelda has always steered clear of DLC. This may be subject to change according to series producer Eiji Aonuma, who stated that Nintendo is looking for ways to create add-on content for the titles moving forward.
Speaking to Nintendo Life, Aonuma said, “We’re certainly looking at different ways to add on content that would enhance the experience for the user – maybe more places to explore or just to enrich the experience beyond what is on the disc.
“But we also have to take into consideration that if we charge for this content then it needs to be worth it for the user. So it’s certainly a balancing an act, but I can’t say that it is something we’re not considering.”
It's hard to say whether the DLC would help to expand the Zelda universe or whether it'd only serve to bog the games down and seem like little more than a quick cash grab. It all depends on how they go through with it. Should they decide to implement DLC in the same way BioShock Infinite is doing it with its three add-on missions, then we wouldn't see anything wrong with it.