They were losing interest
They were losing interest because the "older community" liked the cars, but just didn't like the obnoxious hood scoop on top. They felt it was too "racecar" like. So, Subaru redesigned the newer XT's without a scoop and they just didn't take off like they thought they would. With newer platforms like the Crosstrek catching people's eye, my guess is that the model has started to fizzle out. Even though the newer OBXT's will have the 2.4L motor, nothing will compare to the earlier years with a Turbo EJ motor. Subaru's just aren't the same without the EJ!