Since the insert is aluminum, you don’t have to worry about it being a crack and breaking apart - it’s just a bad surface scratch. So, it won’t affect performance at all. Only way to “repair” it is to replace the entire bezel assembly. Don’t know the price, but will probably be more than a few hundred dollars.
I’d just accept it as a badge of honor for actually wearing your watch and not worry about a replacement until you have it serviced in the future.