I don’t know about that - I was recently in Ireland and many of the folks I talked to picked up on my Minnesota/Wisconsin accent, they said I had a “twang” that many American accents don’t have. I’ve never lived in the Northern parts of the state, just around the Mpls/St. Paul area. Maybe Fargo exaggerated a bit, but it might not be that far off.
I don’t hear it myself, but apparently others do.