I'm not quite sure how to feel about this. On one hand an OS-level SDK (that isn't directly tied to the kernel or glibc) feels grossly overdue, and I'm not sure how you'd go about doing this in a way that is distribution-agnostic. On the other hand, tying your development to a single distribution is quite the antithesis to Linux and doesn't seem to be in the best interest of anyone, including those using the SDK.