Given that chip development has been hitting diminishing returns for a few years it might be time for Open Source to eat the world of processors as well.
It feels like the sort of opportune market that server operating systems, databases and web servers occupied: less of a visual aesthetic and more of a better-design-wins market.
It's not going to be easy - I'd guess that it would take at least 10 years for a project to get any sort of traction outside of a very small niche group.