My 2017 had them, my 2019 doesn’t. They never went completely away but I suggest glass polish or Rain-X.
The rule of thumb is if you can feel the mark with your finger nail, it's too deep.I would be careful with polishing. With an abrasive such as cerium oxide you can polish out small marks that aren't too deep. If they are deep you need to remove much more glass around them. This causes visible distortions in the glass. You won't like the results. Find a cleaner that can cut the oil mark. I would even try a Magic Eraser. Like most methods, always test is a non important spot first. I have also used a product called Miracle Scrub to remove road film which is basically oil residue.