Thanks for the answer!
I would gladly agree with you. But planes passing through each other, like ghosts, are not perceived as flying over each other.
Therefore, visually, it looks very unrealistic.
Moreover, we are dealing with low-flying vehicles, so collisions would be perceived quite realistically...
Or, it is desirable to clearly show the difference in heights, especially when flying over each other. For example, to make a "slide":
One, as it were, rises, and the other, as it were, decreases ....