Yes. It is already an issue of AVX2, which has the hilarious problem that the user must try finding a net performance gain between speeding things up and heating the CPU into thermal-throttle... But I think if an on-chip coprocessor can offload a common task and making it more energy efficient, the thermal issue can be avoided. We've already seen successful applications of cryptographic instruction sets / coprocessors, video transcoding, and the number can only get bigger.