I'm far from an expert here, but these days, it's better to view the instruction set as a frontend to the actual implementation. You can see this with Intel's E

I'm far from an expert here, but these days, it's better to view the instruction set as a frontend to the actual implementation. You can see this with Intel's E/P cores; the instructions are the same, but the chips are optimized differently. There actually have been changes for "today's needs," and they're usually things like AES acceleration. ARM tried to run Java natively with Jazelle, but it's still best to think of it as a frontend, and the fact that Android is mostly Java and ARM, but this feature got dropped says a lot. The fact that there haven't been that many changes shows they got the fundamental operations and architecture styles right. What's lacking today is where GPUs step in: massively wide SIMD.