Comment by ryao
It is funny that you should say that, considering that I was wondering this myself earlier today WRT the Hazard3 cores in the RP2350. It turns out someone did benchmarks:
https://icircuit.net/benchmarking-raspberry-pi-pico-2/3983
The Hazard3 core was designed by a single person while the ARM Cortex cores were presumably designed by a team of people. The Hazard3 cores mostly outperforms the Cortex-M0+ cores in the older RP2040 and are competitive with the Cortex-M33 cores that share the RP2350 silicon. For integer addition and multiplication, they actually outperform the Cortex-M33 cores. Before you point out that they lost most of the benchmarks against the Cortex-M33 cores, let me clarify that the integer addition and multiplication performance matter far more for microcontrollers than the other tests, which is why I consider them to be competitive despite the losses. The Hazard3 cores are open source:
https://github.com/Wren6991/Hazard3
That said, not all RISC-V designs are open source, but some of the open source ones are performance competitive with higher end closed source cores, such as the SonicBoom core from Berkeley:
https://adept.eecs.berkeley.edu/wiki/_media/eop/adept-eop-je...
As for the other problem you cite, the RP2350 has both RISC-V and ARM cores. It is a certainty that if the ARM cores had not been present, the RP2350 would have been cheaper, since less die area would have been needed and ARM license fees would have been avoided.