The 3GS was a great phone, I had one and really enjoyed it, but its time has passed and at the price it's available at you can't reasonably expect it to have all of the latest features.
If Apple continued developing iOS so that the 3GS was able to use all of the features it would severely limit the ability of the software to take advantage of the more powerful new iPhones.
I don't think there are legitimate complaints to be made about the 3GS not being able to utilize the new features, it's an old phone with old hardware that is available for free with a contract. The 3GS receives far more attention from Apple than old Android phones do from Google or the phone manufacturer who made it.
If Apple continued developing iOS so that the 3GS was able to use all of the features it would severely limit the ability of the software to take advantage of the more powerful new iPhones.
I don't think there are legitimate complaints to be made about the 3GS not being able to utilize the new features, it's an old phone with old hardware that is available for free with a contract. The 3GS receives far more attention from Apple than old Android phones do from Google or the phone manufacturer who made it.