No, they revamped their FF program to save them money. But not compared to other FF programs, but just compared to their own previous FF program.

The existing FF program allows people to take cheap $29 (OW) flights paid, and use them on more expensive transcon or midcon flights on awards, including last-minute when the discount paid fares are long gone. Southwest didn't like giving away more expensive flights so easily.

The structure of the new program means you can get about 1 flight free for every 10 you buy, but only in the same fare category and at the same price as the ones you buy. So no more one transcon reserved at the last minute for 8 LAX-LAS hops bought on Ding fares months ahead.

Now, if you want to reserve at the last minute (or for some other flight where the cheap fares are gone), you'll need tons of points (not just double!). So with Southwest's new FF program, most people won't be able to use the FF program to work around high fares.

LCCs look at FFPs differently than legacies. For most legacies, the FFP is a big profit center (so big that some outsiders want legacies to spin their FFPs off as stand-alone companies to increase shareholder value). For most LCCs, my understanding is it's not necessarily profitable, but judged a necessary evil, and (these days) they want to structure it so as to be able to say they have an FFP but to have it cost them as little as possible (rather than earn them as much as possible).

Southwest's original FFP was designed to be simple, and to gain them business. Business has been gained, and so the goals of the FFP have changed. Unfortunately, simplicity also got tossed out the window (because it's not completely money-based, it's got complicated fare category multipliers). "You thought you had enough points for a $300 flight? Sorry, that's only if that $300 was in another column!"