Your fridge may be made from some steel that is susceptible to rust, and the paint protects it. When iron rusts, the iron oxide product is that red stuff, which is not protective and flakes away, revealing more material that can then rust.
Stainless steel has chromium which oxidizes before the iron, but chromium oxide is strong and forms a protective barrier preventing additional material from oxidizing. Though certain environments, such as high temperature or moisture can cause the chromium oxide layer to fail.
Practically speaking, i’m not sure what the best fix would be. If you could prevent oxygen from getting to the bare metal, that should prevent further corrosion.
I switched from ubuntu to debian when 12 was released and it’s been fine. Only thing i was worried about was running WoW via lutris but had no issues.
So when my SO windows pc died we bought some newish parts and i installed debian on it as well. Also installed chrome since that’s her browser of choice. She’s still getting used to gnome, but all she needs is browser, WoW, and libreoffice, which is close enough that it hasnt been an issue. She doesn’t even know how to update the system.