According to newtons law of gravity,all objects fall with the same acceleration regardless of mass,justify the above statement?

As you know friction and gravitation is present on the earth. Newton told this because when we drop two objects from same height at same time in vacuum then both have same acceleration and fall at the same time. Galileo tested this experiment by dropping two objects from the leaning tower of pisa. Vacuum is a place where no air is present. When a paper and a stone is dropped towards the ground at the same time,stone reaches faster than paper because air offers friction to both. But due to the friction to paper by air is more than friction by air on stone,paper falls slowly.