I'm not sure what the gain is here. We have to hope that a standard emerges from a range of extensions - when there are standard ISA's that do the job already.

I'm not sure what the gain is here. We have to hope that a standard emerges from a range of extensions - when there are standard ISA's that do the job already. In the meantime we get lots of incompatibilities. Plus there is the possibility of proprietary extensions which are not available for licensing more widely. Licensing IP to put on SoCs has been common for over 25 years - in fact its the whole basis of ARM's and others business models.