Reach is almost never observed by the person doing it. A nurse who said one steady thing to you in 2019 has no idea she is still being quoted at your kitchen table.
Millions is a way of saying that things travel further than the room. They do — but always by the same mechanism, which is one person telling one other person on a day when it was needed.
You will not see the chain. The part available to you is the first link, and that is generally somebody you already know.