Both my son and I own a Sig Pro 2022's nad we love them.
We are experiencing the same scuff marks on the top of our barrels after shooting them a lot.
I have several friends that have experienced the same scuffing, so I believe it's normal wear.
That said, I'll probably polish my barrel to get the black entirely removed.
If you do it you should not remove any metal, just the finish and be aware it is more prone to rust w/o the finish.
Just keep it oiled.