Well, the Israeli fort line along the canal and their fortified passes were no defence in depth. they did intend to hold the Suez line; the depth of Sinai rather served as buffer against the long-range artillery harrassment of 70/71 than as a planned space for manoeuvre IIRC.

The Egyptian defensive positions didn't practice much elastic defence or defence in depth either. They did even lack the necessary effective mobile reserve to handle the later breakthrough.

The Israeli armor brigade was so terribly imbalanced in part because that saved much active-service personnel in comparison to a forward-deployed well-rounded brigade. The example was thus a rare and special exception.