I should have added a caveat, I actually agree with you and I, too, was skeptical of the fact this has been happening. However, since the FCC released an official document about it I figured it was worth mentioning as a theoretical possibility. I am unaware of many cases where the FCC spread urban legends without getting actual complaints, so people presumably have actually been complaining about this happening to them to the FCC, or at least them believing it's happened to them.

The "can you hear me" call would have to take place AFTER a scammer had already charged your card for a dubious service. They would (probably?) have to have a merchant account with a payment processor for that.