As I sit at the airport waiting due to a flight cancellation, it crossed my mind that with the switch to spend-based points earnings and the focus on 1K+GS, this could make sense to UA. File this under Captain Obvious, I guess.
Under the new system, the normal flyer or credit card holder (not FT reader) will have much less ability to redeem for affordable flights (even if they think they will, and even if they don't, they don't know the system's been changed on them) since they just don't earn that many miles to begin with, and the high spend/earn flyers are earning so many darned points that they just won't care about spending 45k vs 25k for a domestic flight (my anecdotal example is a GS relative who spends ungodly amounts of cash on last minute and international business tickets, but has zero knowledge about how the game works or FT).
UA wins at the bottom by selling Chase cards and the dream of free flights, with maybe every now and then someone scoring a discounted mileage ticket where a seat otherwise would have gone out empty (zero cost). UA wins at the top by showering miles on high spenders who don't really notice the difference between 25k and 45k to get their kid home for the weekend.
Then there is the whole universe of FT readers which is like 1/10th of 1% of the UA universe.