On my 2014 DS, I had just the stainless steel kickplate at the front door and stainless steel step covers. Over time, the kick plate got scraped up (purpose of a kick plate) and the steps got marks and scrapes.
I attempted to polish them out and always made them worse. Today, I was determined to figure out how to polish the scratches out. I have some drill driven buffing wheels with two sticks of polish, one for soft metal and one for stainless steel (Harbor Freight kit). I found using the stainless steel compound roughed up the surface, but was good to get out deeper scratches.
The marks on my new 2019 kickplate were more like abrasions and not very deep. I decided to try some Flitz polish and a Flitz drill driven buffing wheel I had, to remove them. (Mothers polish and a Mothers Power Ball would probably work the same, I just like Flitz better).
I dabbed a small amount of Flitz on the kickplate and started buffing until it disappeared. It took about 4-5 applications until I eliminated the marks and returned the shine to the stainless. You only need small amounts of the polish, polishing until it disappears and then add some more.
The reason I brought this up......…I know at least the Dutch Stars have the stainless steel kickplate as standard and many have the full trim package. I was tired of looking at the scrapes on the kickplate and wanted to find a good/easy way to remove them. I figure they'll need buffing every six months or so, but now that I found the right combination, it should only take a few minutes.