The first-flinch reason assumed by many for not going with the latest and "greatest" is because people don't like to deal with change.Try playing a FPS or racing game with bluetooth. It's not cool hearing the the sounds with 1/10th+ second delay after you fire or hit something.
Then theres any music apps e.g. samplers, dj programs, garageband where you need as close to zero latency as possible or they are unusable.
There are technophiles who love technology... for them, newer = better. Tech companies, like Apple, love these people.
Some tech endures because it continues to serve a purpose that the newer tech doesn't. Wired audio is one.