So in essence they are usable with more maintenance and the caveat that they are on borrowed time?
correct, once the coating is worn through the damage is already done.
Depending how bad the scoring/wear is will dictate how quickly they chew up seals or drag dirt in, and if they are really bad there maybe extra play in the bushings or ‘notchiness’ to the travel.
But if it’s just light wear then sometimes it can be hard to even feel it in use so just crack on with using them, keep an eye on them and plan to replace when you can (or want to).
*there are companies that will replace the stanchions, and seem to be getting good reviews, but still some questions about the method they use to get the old ones out and fit the new ones as essentially they are an interference fit at the factory so not sure if I’d eve trust a fork crown that had had the legs pushed in and out without knowing more about the process.