EDIT: Fix thanks to some work from @SirPenetrator , Editting your Engine.ini can force Anti aliasing On and also can
also enable Supersampling. VIDEO below comparing the settings
Simply navigate to your folder containing it:
Open Engine.ini in your notepad and add the lines
(add the line ' r.ScreenPercentage=150 ' under those for Super sampling, 100-200+ be warned as this increases GPU usage alot!)
I.e the file should look like when your done (ignore r.ScreenPercentage=150 if you don't want to add Supersampling)
Here is a video comparing the settings
Keep in mind this image doesn't do the issue justice alone, almost all sharp/flat edges has these flashing effects on Very high or other AA settings at 1080p.
This occurs while the image is moving, i.e character moving or scoped with natural movement.
This causes especially on maps with longer ranges with lots of buildings an extreme difficulty to quickly distinguish when a target pops out of a window or is visible.
Since all the flashing effects from the poor aliasing on screen make it very hard to see the contrast of a soldier's head flashing out of a opening, when literally every geometry in the game is flashing at you.