Plain and simple. Be it Galvanic, High Density, Insulating or Soft Foam, it is still synthetic material. It would give more reasons to pick the feat than the few available, since it's a versatile component used for many types of armor. I don't mind going naked caveman against electric threats, but enhancing the option of protecting oneself by crafting at least gives a range of survivability, if lesser, other than getting the Tesla Armor. Same thing with cold protection of insulating material vs Bison leather. If the idea takes away reasons for investing stealth skill points, it can be a lower percentage while keeping the fabric bonus the same.
Also, many leather outfits look better without overcoats, so compensating with the padding would be nice. But that's a minor thing.