Somethings changed in the renderer where materials that have complex reflectiveness in the roughness layer seem to get washed out. This affects even vanilla BI assets but does not have as profound of an impact. On most of the BI assets it depends on view angle but weapons such as the AK-74 it is evident and jarring as it appears to have some aetherial glow on its edges or just a really lubed up, things like the handguard become very washed out. It's like its trying to project light as a reflection even when there is no direct light (i.e in the shade or low-light) which causes it to really pop.

I have tried tweaking a few settings to try and reduce it such as Dielectric Reflectance but to no avail it's still very profound at least on my stuff. Below is a collection of images showing the MH-6J at various angles as well as vanilla assets like the S105 and AK-74.

On the stable branch (1.6.0.119) everything is perfect so dunno what exactly changed in the rendering between then and now but really hurts the amazing texture work done on this particular mod and it just affects all assets in general whether its a modded weapon or vanilla it just depends.