I tried every approach possible, making my own Noise blur from Grey 50%, scalling it, making it a Pattern, using that Pattern on a Clipping Mask, using that Pattern on Bevel Texture, can't achieve it as I can't remove the Bevel sides, I don't need that, and even simple Blending Modes.
The best I'm able to pull off is a Linear Light (as you've demoed)or Exclusion blending, but since it's Grey ti's darking the whole folder icon? And at best, it's just polkadotting dark spots around it. I tried a bit of putting Motion Blur horzontally to stretch it too, but that only trailed the dark spots. Is there any better way?
Can you share the PSD or Cloud PSD file here so I am able to dissect and implement it myself?
PS : what's with the Gradient Overlay, and where is that placed in this approach?