I doubt that the primary motivation for Magenta is to eliminate the GPL'd Linux kernel from Android. A much more practical way to do that would be to use one of the BSDs.
They also deprecated GCC from the NDK, going forward only clang will be supported.
GCC is still around, because just like it happened with Apple, there are a few features that clang still lacks in order to fully replace it in the context of Android.
GCC is still around, because just like it happened with Apple, there are a few features that clang still lacks in order to fully replace it in the context of Android.
Brillo has even less GPL components than Android.