Earth pulls all objects downward by the same gravitational acceleration of 9.8 m/s². But the force of gravity exerted by Earth on an object still depends on its mass. An object with a greater mass has a greater force of gravity (also called weight).
Flat-Earthers claim that if greater mass means a greater force of gravity, a bowling ball in a vacuum should fall faster than a feather. In reality, they confuse acceleration with force. Both fall at the same speed because the gravitational acceleration is the same on both, but their forces of gravity are different.