Prior to the release of Tears of the Kingdom, many skeptics would revel in referring to Breath of the Wild's upcoming sequel as "$70 DLC." The reason for that was twofold: first, TOTK was not only based on the exact same version of Hyrule as BOTW with the same map, but it also carried over many of the same character models, monsters, and story beats as its predecessor. The second—but no less important—reason TOTK was being referred to as "BOTW DLC" was that the producer of the game, Eiji Aonuma, revealed in an early interview with Kotaku that TOTK first started as a series of ideas for BOTW DLC until developers realized they had more than enough new content to just make this into its own separate game.
Source：https://www.cbr.com/why-totk-doesnt-need-dlc/
