Maybe, but why?
The answer to the OP's question is maybe it is OK to store in the can, but why take a chance?
Tin cans when most of us grew up were made in 3 pieces (two ends and a rolled body) with three seams that were soldered with lead. The lead is the source of the concern and the leaching process is greatly accelerated by opening the can and introducing air.
Today, less than 5% of cans packed domestically are 3 piece cans and instead are made in two pieces (body and bottom in one piece and a top) with only the top welded on as opposed to soldered. Even the 3 piece cans are generally welded except for some dry goods like coffee. Lead leaching doesn't occur in dry goods.
These welded cans would be safe from a lead standpoint, but not very easy to seal tightly, so why mess with it? One overturned can that has been covered with plastic wrap in the refrigerator will offset years of time saving by storing in the original can.
However, the biggest danger is that many foreign packed cans sold in the US still contain lead soldered seams and it is easy to assume that your favorite brand was made in the US until you read the label carefully.
Like all food safety, I think it is better to develop a set of behaviors that assure you are protected even if they are unnecessary in some cases. That way you eliminate subjective decisions that may or may not be correct.
In this case, for me, that means never storing food in their original cans.