Seemingly, the most mundane possibility here is they exist, they're not rare at all, but "not rare" on the global scale of all galactic and larger superstructur

Seemingly, the most mundane possibility here is they exist, they're not rare at all, but "not rare" on the global scale of all galactic and larger superstructures in the observable universe doesn't mean you're necessarily going to find them in South Dakota in some specific 280 day window.