People calling totk an "immersive sim" merely confirms to me that the genre label is meaningless and arbitrarily applied to any action game people think is sufficiently sandboxy (except actual sim games, which are clearly not """Immersive""")
I recently heard someone call a top-down CRPG / survival horror game an "immersive sim." it has turn based combat. the industry made a mistake when they named it this, maybe "Deus Ex Clone" wouldn't have been that bad after all (even if calling System Shock 2 one of those is incredibly silly)