So, you can use a map etc. Fine. Good for you. Doesn’t mean it’s inconceivable you’d be affected. GPS is also used as an extremely accurate method of timing in industries that require it, such as banking and the financial sector.
Sadly , while I am not the sort of person that reads things like this and immediately thinks about investing everything I own in canned food and shotguns, and I am confident the finance industries have taken the relevant steps to mitigate this already (while they do seem to have let the IT on the consumer side get old, The IT used in the trading systems is usually state of the art (after all, if a stock transaction is delayed by even a millisecond, it can lose the company tens of millions of pounds) it is still possible that any member of the population could be affected.