The discount applies only to base fare and Frontier pricing is mostly about taxes and fees, including mandatory booking fees. So you may not be saving as much as you think in percentage terms. Fronter base fares aren’t most of the cost of a ticket, after all.
But this is a very good deal indeed for those with status, including those who took advantage of status matches and who have free Frontier status (and likely won’t pay add-on fees as a result).