my memory sucks but i think there's been only 3 seasons where all members of a final 3 got at least one vote? the closest f3s are still only between 2 people like Ozzy and Yul. here i know there have been close f3s either between two finalists or all three finalists having a chance. there's also been an 8-0-0 of course.
honestly i think both formats are fine and we should use both around about equally, or if we want to be realistic and emulate the show (a debate) we should use f3s nearly all the time.