The definition of insanity is doing the same thing over and over again and expecting different results
The cutoff points racing is exciting to the broadcast partner that believes the racing lacks entertainment value without it, and some media members for whom it provides easy content to obsessively cover in near autistic fashion.
It does not result in larger audiences or greater engagement for cutoff races. For most fans, the "tension" and "drama" created is watching on pins and needles hoping that "the right" drivers happen to make it in based on season-long performance, which should always be the determiner of auto racing championships. When it works, it works by accident.
As has been said, if they insist on a winner-take-all-finale (which to be fair has resulted in a larger audience for that one race), they would be better off with a 35 + 1 format in which the top four after 35 races advance to the final race.