I don’t see the value in a formal business plan at all and so I would almost agree with your made up quote there.
I mean obviously you need to have a plan for your business. But writing it down in some formal way seems like a waste of time.
Perhaps there is value in writing one in order to coalesce your own thoughts if you are that way inclined, but it’s certainly not going to convince anybody of anything that wouldn’t be convinced by the conversation you would have instead.