The ommitte empers have been awareof simd for a long time and asking that. So far they have either not agreed, or because they have seen no need because autovectorization has shown much promise without. (that is both of the above are true though not always to the same people)

multi core is where languages have had to change because the language model of 1970 wasn't good enough.

It was an example among many others.

How does (FPGA, HiLow, Havard, CUDA, MPI,...) guide ISO C?

How should they? in some cases they have decided that isn't where they want c to go, in others the model of 1970 is still good enough, and in others they are being slow (possible intentional to not make a mistake)

So C isn't about being designed close to the hardware after all.

it is designed with careful understanding of real hardware. However that is not close to any particular hardware.