Even outside of scams, creating a sense of urgency is a tactic often used in sales. You want the customer to feel like if they walk away now they'll miss out on a great deal.

When I worked in travel this might be literally true if there were only a few seats left on a longhaul flight or hotel nights on their dates. But it was always good to get them to commit there and then as you would do all the work setting the holiday up and a colleague might get all the commission if they came back in a few days. We didn't bully or pressure people but we had ways of encouraging them to book on the day.

In a scam, there is always an element of time pressure. It could be a guy selling something out of a van. "I'm about to drive away and you'll miss out on this deal". But more commonly nowadays it's "We're the bank and someone else is using your credit card right now. They need to be stopped immediately."

In this particular situation, the thing to train yourself and your elderly relatives to do is not to give out any information, hang up and call your own bank directly. Not using a number in a text message or given by the caller. The number from your bank's website. If the call is genuine, you'll still be able to deal with it. These it's way more likely that this type of call is a scam, so that should be your assumption from the get-go.