[renox]

Except that by having fewer instructions in the ISA you may have to increase the number of instruction executed by the CPU which is what matters for performance/efficiency.

Has RISC-V made the good tradeoffs? We'll have to wait a long time (until someone tries to make a high performance RISC-V instead of glorified microcontrollers) to know..

Note though that the RISC-V is a cleaned up MIPS ISA beside being open it doesn't bring much novelty (nothing to improve security or GCs) with the (significant) exception of the (unstable) vector ISA.