The fact that cold calling was expensive was a signal that the caller was legitimate.
In the era where calling someone on the phone is cheap and highly optimized, getting a phone call is not a signal for quality.
But back in the 1980s that wouldn’t have been the case. If a human being picked up the phone and called you, you would be more inclined to listen to them, simply because you knew it was expensive for them to call and it happened infrequently. Phone spam didn’t become a thing until much later.
In the era where calling someone on the phone is cheap and highly optimized, getting a phone call is not a signal for quality.
But back in the 1980s that wouldn’t have been the case. If a human being picked up the phone and called you, you would be more inclined to listen to them, simply because you knew it was expensive for them to call and it happened infrequently. Phone spam didn’t become a thing until much later.