I'll give you the flip side of the scammer's deterioration of trust in the phone... a few months back I got a phone call from what appeared to be my bank, and they were asking me about a fraudulent charge that I didn't recognize. Worried that this was the beginning of a scam, I delayed a bit on the phone while I logged in independently to my bank account... and lo, yes, indeed, there was a fraudulent charge to my acc…
For those worried about a situation like this, I set up automated purchase alerts on my credit cards and withdrawal alerts on my bank accounts. I see it all in close-enough-to-real-time, and it's helped me catch fraud before the banks did at least twice in the past few years.
It's nearly real-time. In any drive-thru I'll have the notification on my phone before the card is handed back to me.