I saw many people reporting the disappearance of the golden skin and I checked for me at least the skin always appears when starting a new game (both pre and post patch) but when a save is loaded the skin always is absent again (I saw this happening both before the patch and after, even with a new game with the patch)
I have the GOG version patched
Is a minor bug and not affects the gameplay, but maybe can affect other cosmetic changes in the future like the golden/silver jetpacks