The end of the Wright Amendment was definitely a problem for OKC as a WN station. Prior to that, Missouri getting added to the list of states where you could fly from DAL before going onward didn’t help either and I believe that’s when OKC-MCI disappeared or shortly thereafter. But for all the losses they were the first to fly N/S to the DC area with the BWI flights. They added DCA, which folks in OKC had been clamoring for forever. BNA going daily is a nice alternative to STL. Also, isn't MDW year round now? And even with the loss of 3x daily flights to DAL, the net number of WN flights is zero with BNA going daily and adding a 4th HOU and 3rd PHX frequency. So clearly WN found it more profitable to connect OKC passengers through other “hubs” and make better use of the gate space at DAL.
I think the biggest problem for WN at OKC in the last couple years has been AA. 8-10 flights/day to DFW, 4-5x to ORD, 2-3x to CLT, 2-3x to LAX, 1-2x to PHX, 1x to DCA and soon to be 1x to MIA is a lot of options. Really all they have left to add is LGA. I also think AA is making a dent with corporate accounts around OKC. While this is only one example, a buddy of mine works for one of the decent size oil companies in OKC and used to fly WN to MAF and HOU a couple times per month. Now he has to take AA through DFW unless the WN N/S to HOU is absolutely necessary. He’s racked up a ton of AA miles and status and now wishes he would’ve been flying AA all along.
They added DCA nearly seven years after first promising to add it. BNA going daily? News to me...and it's about damn time! But the OKC chamber of commerce went to WN back in 2011 and begged them for a Bay Area flight for business travelers as well as connection opportunities in CA and the PNW...WN let them eat silence. They then went to UA re: SFO. UA immediately jumped on it. When WN dumped the OKC-ATL route, the airport and CoC pitched a fit, as this severely reduced the southeastern connection opportunties and gave DL impetus to jack up fares. WN responded with silence. There has been a long history of give and take between WN and OKC.
As to your friend going AA more, he's not alone...as I've had to do that numerous times the past three years...and I really don't care much for them due to service issues. But their schedule is 10x better than WN's out of OKC. But if we're using the PDEW between OKC and the metroplex as a gauge for why WN is canceling the route, then we'd better watch out, because AA and their 8x daily (with 7 on mainline) to DFW will be next