'For those who don't know…'

In some writing spaces, there’s an actual physical list of clichéd words and terms on a wall- phrases that have been overused to the point of being meaningless. It’s a good practice to remove crutches and help sharpen writing.
One of my personal crutches that I’ve been thinking about lately, which is “for those who don’t know.” I use it when we have an expert guest on and I want the host to prompt them to give a basic explainer on the topic at hand. For example:
“For those who don’t know, what is the first-past-the-post voting system?”
“For those who don’t know, why does the U.S. think Canada is unfairly subsidizing softwood lumber?”
“For those who don’t know, what is geoengineering?”
It’s a way of making the topic accessible while demonstrating that we, the journalists, already know all this stuff. This is for the benefit of the listener, not us.
I’m wondering if that’s necessary. If a host were to start a conversation with “What is first-past-the-post voting?” would listeners at home throw their hands in the air in frustration at their ignorance?
Or would it be pretty clear that this is being done for the benefit of establishing the basics before moving on to the more nuanced portions of the conversation?
Interested in your thoughts.