This page says:
When you make a telephone call, you ask if you can speak to someone. You don't ask if you can 'talk to' them.
Hello. Could I speak to Sue, please?
But in fact, a lot of native people says
Hello. Could I talk to Sue, please?
See this English teaching video at 4:22
"Can I talk to Phil Watson, please?"
So, who is right?
"Hello. Could I speak to Sue, please?" or "Hello. Could I talk to Sue, please?"? Which one is correct?