software used to be hardware limited, and therefore efficient. Today Software relies on many more transistors per joule to compute a number of operations in high-level languages. I'd agree 22nm isn't leading edge, but foundries like Skywater could theoretically provide more options at 65nm and 90nm in coming years that are fully open source, except for the cost of the foundry technique perhaps: https://riscv.org/wp-content/uploads/2018/07/1130-19.07.18-L...

Yes, I think we might be talking about slightly different things. I don’t really see OS model working for higher-end / leading-edge chips.

In segments where chips are almost an interchangeable commodity and the R&D cost might be insignificant relative to manufacturing/foundry it would make a lot more sense.