The acid ate the finish, and there is no way to bring it back that I know of.

You could spray paint it to make it look less unsightly, but over time that paint will wear off.

I agree the surface is ruined. You could also try some past car wax; apply, let it dry and buff with a soft cloth.

use Gel Gloss and some elbow grease next time

Wow! May be chrome paint over plastic, real chrome finish would not be ruined by vinegar. They do make a chrome finish comes in a spray can but it would be shiny not brushed. My front bathroom faucets are 40 yrs old & still look new. But I always insist on real metal with real chrome over it. Day coming when that may no longer be possible. Do they have any warranty?