Car interior protectant....

[Kachingg]

And me lol.
A damp chamois works really well! As does a slightly damp micro fibre cloth but the chamois gets any marks off the fabric really well.
Its the ‘protection’ bit - as in UV protection...that makes me think I need to use a product of some sort??

In modern cars i would not bother my old mark 6 is nearly 9 years old and has been outside all its life with just the damp cloth method used on dash its still 100% ok no fading/cracks or other noticeable deterioration

[Ozsko]

I think manufacturing technology surrounding plastics has overcome the ageing problems and cracked dashboards etc are a thing of the past.