I agree that with Auto brake working there is no need to keep the feet up. In 747 classic without RTO and free rudders was tricky. In airbus you won't have AB working below 72kts but stopping is not an issue at that speed. Slippery runway crosswind engine fail feet up differential braking helps in keeping it straight as well stopping. Feet up you have to use rudders with heel or lower half of the foot for directional control otherwise inadvertent brake application will send brake temperatures up or disconnect AB. Landing is different because AB is not a necessity and limiting landing distance you are in a position to quickly apply both or differential braking as required. Airbus rudder pedals are flat perhaps made to keep your feet up.