"I find brass wool very harsh on a tip's plating, techs on the shop floor throw Hakko's brass wool into the garbage."
To each their own.
Possibly my most used tip is a 3mm TFO bevel. This collects residue like no other tip, due to the design and how it's used. After 4 or 5 years of seeing very heavy use and being cleaned solely with brass wool and brass tubing, it DOES show a little spot of damage on the edge of the chrome. This damage is the spot where I have dragged the tip against the inside bend radius of hundreds of thousands of SSOP gull wing IC leads.
If the tip were to wear out eventually, I would just buy more. It has paid for itself several times over, already.
There may be a difference between tips and techniques, too. I am using genuine Hakko tips. And I don't jab into a ball of brass wool. Over the years, my Hakko brass wool is balled up on the left side of the holder. I insert the tip into nothing but air, and swipe it against the brass wool on the way back out. This keeps the wool from catching on the leading edge of the chrome.
Aside from the hardness of the wool (which brass is softer than chrome), you also want to avoid too high of a localized pressure at any one point, esp near the edge, while cleaning with something like a brass tube/edge. Getting too much pressure on the chrome can cause the chrome to bend beyond its elastic limit and chip out at the edge.
Any rate, a wet sponge or paper towel is not aggressive enough to efficiently clean off the residue, once it has taken hold. The residue is very hard and very brittle (more brittle than the chrome) and is held onto the chrome, mechanically, by locking into surface defects. The brass tube makes short work of it. Once you break it up, the smaller bits are easily wiped and/or dissolved away. The brass tube is pretty close to ideal for "catching" the residue and quickly chipping and cracking it...well before the same would happen to the chrome. As long as you don't exceed the elasticity of the chrome, causing it to chip, you will not do any cumulative damage through abrasion.