I have added 6 screenshot to better illustrate the problem.
Image 01 - You can see the dot sight is not shaded by the player at all and the glare is there, so far so good.
Image 02 - The dot sight is only half shaded by the player (see the shadow line) and the glare is still there in a
reasonably realistic position, still good.
Image 03 - You can see that now all of the dot sight is shaded by the player but the glare is still there,
there is the issue of the shadow of the player on the ground, that is blocking some of the glare,
this is obviously some sort of Z depth fighting issue, since the glare anyway should be front of the ground shadow.
However, the sight is completely shaded by the player and therefore the glare at that stage should vanish completely.
Image S01, S02 and S03 illustrate the same problem only with the 3D scopes
For people who think anti reflective coating on military scopes is funny:
Please, fix it.