Remember this; polishing (anything) means removing material so as to smooth the surface and reflect light without scatter.
Key words; removing material
Is your gun running currently? Does the gun's accuracy meet your needs?
If yes to both, there is NO
reason for "removing material"
and should be left alone.
If no, you got bigger issues than vanity.
I will share with you my well/over used mantra; "Never change a running assembly."
What's to gain?
This also applies to the bushing/barrel interface on guns so equipped.
I see no contraindication to polishing the chamber area where visiable in the ejection port but stay away from the locking lugs and bushing contact areas.
AND; if it's a carbon steel barrel, it will rust. I guess that is