No, there is no specific point on Earth where all directions are "down." The concept of "down" is relative and depends on the reference frame and gravitational forces acting on an object. "Down" typically refers to the direction in which gravity pulls objects toward the center of the Earth.
On the Earth's surface, the direction of "down" is perpendicular to the local surface and points toward the Earth's center. However, as you move across different locations on Earth, the direction of "down" changes due to variations in the Earth's shape and the irregular distribution of mass. Additionally, the Earth's gravitational field is not perfectly uniform, so the strength and direction of gravity can vary slightly from one location to another.
Therefore, while there may be points on Earth where the local direction of "down" aligns with the plumb line or the normal to the Earth's surface at that specific location, it is not possible to find a single point where all directions are "down" simultaneously.