Higher fov seems to allow less mouse movements from high to low shooting at long distance. On a far away target it seems that I don't have to move the mouse up as much but making it more sensitive to how far. However, I don't know if this is just a visual distortion or a physical and visual distortion. The jump point also appears to be more in front of the player with a higher fov. My jumping improved at 120, I really don't care why.
I don't see the point of arguing if theres a real difference or not. If the distortion helps you play better for some individuals, which is seems to do, then what does it matter if or why.