There is a pretty big reason why that is the case.
Basically, even something like mapping takes 20-30 different programs to accomplish, many of which are licensed, so they cant be licensed for public use. The Frostbite engine was built with performance in mind first, and not for modding. To do so would have needed to them to skip some of the stuff that lets BF3 look like it does.
As for the blue filter, that is explained in there too. The mod modified memory values, and such an exploit could be used to cheat by modifying health, gun damage etc in real time.
Basically, DICE doesnt have anything against mod tools, its just an undertaking that is way too huge for what it would bring, and believe me, I would love nothing more that PR in frostbite.