They use HEAVILY LOD

At distance soldiers are simple animated meshes without shader,
i htink it's only on close that sss shader is used !

Even more ; the action is so intense and fast you don't have time to
look at it , a simplified one could do the job, i'm sure they have
some good optimisations similar to LOD even for shaders

What is obvious is objects like rocks poping up : they could have used progressive transparency like in Oblivion ?
LOD is the key

But i have a very good machine , and it's not sufficient

In fact each time lot more polygons , effects ,shaders are needed to be displayed for next gen games, so each time you must upgrade
hardware caus more power needed even with optimisations.

or you must put parameters all to LOW to have max fluidity like in Crysis

sss for 3DGS anyone tried to do one optimised and fast ?