Based on my experience, I think there may be some wrong assumptions about using steel wool on chrome.

Since I've used it so many times, even on fine chrome, with great results, I don't think the steel wool itself can scratch chrome, although it obviously can remove loose chrome flakes.

The problem with fine scratching, as I see it, turns out to be the presence of abrasive material (sand, silica dust) that in on the surface before cleaning with steel wool. Never use any scouring pad, metal or otherwise, on dirty chrome, and never use any scouring pad such as ScotchBrite that contains relatively coarse abrasives.

I might add that a very coarse steel wool or very heavy rubbing could possibly impress the thin chrome layer into the softer copper layer below, and appear as scratches, but steel and rust itself don't seem to be hard enough to actually scratch the chrome, again based on my experience.

So, before using wool pads to remove rust specks and coloration, I advise to scrub first with soap and water.

And, for the totally shot chrome on bolts and hardware, I have a deburring wheel (think compressed ScotchBrite) on my grinder that will polish the surface bare in preparation for some metal polish and regular waxing or oiling to prevent rust. This gets them on the road looking sharp, and I can get new hardware or re-chroming at a later time. I did this with my 1962 Continental's front derailer cage, and have since found a NOS Huret cage on Ebay.