That looks like the rather annoying 'even film of dust' that modders like to coat the internal glass with. Very annoying in low sun. Select it in CM showroom and lower the ksDiffuse value.
Or swap in a better 'dirty windscreen' DDS like this one:
MediaFire is a simple to use free service that lets you put all your photos, documents, music, and video in a single place so you can access them anywhere and share them everywhere.
www.mediafire.com
Or try this:
https://www.nutrimatic.cc/assetto-corsa/reducing-or-changing-windscreen-dirt/
Edit: ignore the above if the windscreen is tinted. Hard to tell from your images. Mods with tinted glass should be binned immediately.
Edit: oh, it's YOUR car mod?
Edit: what happened to the RS Spider?