It’s not a case of splitting people up — rather it’s just that the seating algorithm has been configured to treat each person as an individual rather than attempting to keep groups together. Random means a 1-in189 chance that you will get any particular seat.
It’d be interesting to research whether there’s a safety implication with this approach — in the event of an emergency will people exit directly or will they attempt to help their loved ones at the other end of the plane?