” Foods cooked (effectively sterilized) in steel cans will last through the next ice age”
Not always. I did have the acid in a can of tomatoes eat through it!
I think in the past people used common sense. If it smells or tastes bad...DON’T EAT IT! I also suspect use by dates are a legal CYA to protect companies from idiots who will eat anything and then try to sue if they get sick.
I had a can of sauerkraut do that, the lesson here is jar your tomatos and kraut. :)