An open world is a level or game designed as nonlinear, open areas with many ways to reach an objective.

Open World Game - Gameplay and Design

Ocarina of Time’s maps are NOT designed as non-linear areas with many ways to reach an objective. Areas in Ocarina of Time are funnels that direct a player to the exit or to the entrance of a dungeon necessary to the linear progression of the game.

The only way to get to Dodongo’s Cavern is through the Path to Death Mountain. The only way to get to the Water Temple is from Lake Hylia. The only way to get to the Shadow Temple is from Kakariko Village Graveyard. While some areas connect, such as Zora’s Domain connecting to Lake Hylia, or Lost Woods connecting to Goron City, these are not “non-linear paths offering many ways to reach a goal.” Each of these is an item-gated shortcut, requiring progress in the linear game to obtain the necessary items to unlock the shortcut.

Ocarina of time says “I know you want to go through that door, but it is locked. Come back when you have the correct key.”

An open world game says “What is a lock? What is a door?”