You don't need to submit all of those, but generally these vectorized DSP functions are parts of decoding straight out of the spec, so there isn't a new way to do it.
Sometimes there is of course. In that case you can get someone else to help, or one platform just runs ahead of the others.
Right, but you see my point, don't you? For every set of intrinsics you'd need to know as a contributor if the vectorized code was in C, there is an assembly language and a set of intrinsics you need to know as a contributor today. Moving to C wouldn't increase the set of things a contributor needs to know.
Sometimes there is of course. In that case you can get someone else to help, or one platform just runs ahead of the others.