Simple Green can promote rust steel IF you don't rinse it with clear water and IF you don't treat it with oil as soon as your done cleaning it. Cleaning oil off any steel will allow the steel to rust faster because the oily film that was protecting the metal and now is exposed to the water, air, acids, and minerials that helps steel to oxidize, and this oxidation is known as rust. And if you don't retreat the exposed steel to somesort of oil then it will rust faster then normal. Exactly what happens to cast iron skillets.
The same thing can happen to aluminum if you clean it with Simple Green! Aluminum is very impervious to what nature will throw at it except acid rain, alklin soil or other metals touching it. These things can cause the aluminum to brake down much the same way as steal & turn into a powder, aluminums way of rusting-actually corrosion.
For the above reasons is why I haven't used Simple Green for years, but I never mention it here because many of you clean your chains and bikes with the stuff and shot me down for even mentioning that Simple Green could be problematic as the US military discovered. But if you recoat with oil, like you would with a chain, then there shouldn't be a problem.
I prefer used motor oil, that's why I don't clean my tools after using them other then just wiping them down. Used motor oil has had any acid in the oil originally burnt away thus there is no acid left to pit steel.
Don't forget that good quality tools are made of chromium steel and are pretty much impervious to rust. I have a few tools that are 50 years old with no rust and some that have a patina which looks like rust but really isn't, not sure what the tools with the patina are made of but whatever it is their tough and have been used a lot since their common size tools (their also heavier then the equivalent modern day tools).
There also has been some controversy about WD40 was causing metal to rust over time, but the WD40 company has disputed this, and I, as well as others I know, have never witnessed this or heard of it.