Well there is a simple remedy, and it is the same like for rust. Keep it dry. All microbial live needs water just as much as larger liveforms. If it is dry it canโt spoil, even if there is microorganisms on it. They might be alive, but theyโll be in stasis without sufficent accessible water. accessibility is also important here. E.g. salty water or water with high amounts of sugar are not useful to most microorganisms.
We all know how easy it is to keep a car dry in the PNW.
Bro rust isnt the issue up there its damn moss growing on your car. If it sits too long (or even if it doesn) shit starts looking like treebeard.