I wouldn't be surprised. We've already seen the end of the manual transmission. 2WD is slowly disappearing. We may be seeing the end of standard and extended cab trucks as well.
Like someone else said, manufacturers will make what sells. Right now the crew cab is overwhelmingly popular, especially with the 5.5' (short) bed that leaves the trucks with pretty much the same wheelbase as the extended/double cab 6.5' (standard) bed.
Keep in mind that most people by far don't use their trucks as trucks. Even the ones that own 2500/3500 or Super Duties. Cab space is more important than bed space. You're outnumbered 100,000:1.
In the future there will only be two types of vehicles: Hatchback SUVs/CUVs, and crew cab pickup trucks.
