Whatever the 1.5% ARM royalty fee is for your org: https://www.codasip.com/2017/04/11/risc-vs-impact-on-process...

For someone like Western Digital, that's probably a huge deal. I don't think it saves the RPi folks much. I suspect they get a loss leader deal. The total volume can't be that high, but it's good press for Texas Instruments.

Around 0%. Its not about cutting cost, its about finding new ways of continuing hardware effort. Broadcom has ~zero incentive screwing with outdated SoC at this point, but it might be relatively easy to sell company board on RISC-V research initiative.