everyone pushing penetrol or fancy sealers is basically just shilling for chemical companies who convinced everyone bare iron cant survive outside on its own. structural collapse from natural oxidation takes decades unless you literally submerge it in seawater. the heavy crust literally seals the core metal underneath once it stabilizes if you just stop messing with it. people waste 40 bucks a can on glorified mineral oil because they swallowed the industry fearmongering about structural integrity