Well hell.... there's the problem! Maybe they should put a cap on it
I don't know too much about the cap-less thing.... do they ever leak? Seems like it would be the same premise as an air-admittance-valve on house plumbing. Things can go in but not come out. And those things fail constantly. I realize I'm down a rabbit hole here but it just seems extremely unlikely that the paint would only fail under the fuel door and it would be caused by something other than fuel.
Paint fail? Dunno, but near gas fill, hmmmmm. The capless vent system is 2 part, with a upper and lower vent system/valve. Not heard of failures as much as venting issues causing issues on filling the fuel tank. My take is this: A lot of PPL, and I am guilty also: Will fill a tank till pump clicks off, then force more in there to top off tank. A lot of PPL have said, doing this forces fumes and such through system into vapor cannister ref EPA, and not good. Well, I am no mechanic, but have read about this issue. NE WAY, I now fill till stops, wait 30 seconds, fill to second stop, and that be it. But I also do not fill my tank on the highest speed. But there have also been tank issues and filler neck issues where there may have been a TSB and new parts ref tank fill issues. Kinda luck of the draw, unfortunately. All IMHO.....
ADDED: 2 part system is why RAM also has a specific funnel designed to put fuel in the gas tank by means other than a gas pump, ie., like a gas can, and the funnel comes when you buy your truck and is located with the jack. A lot of PPL do not know this. I personally, when I had my ED, and was adding Cetane to the tank, had a "long" skinny funnel that I could put in the tank to open both valves to add the "Diesel Kleen" to the tank, instead of using given funnel and have to deal with those fumes in the cab if you kept the "issued funnel" in the truck.