(Personal opinion) I get the impression that RISC-V-related discussions often lack of awareness of prior work/alternatives. A large amount of (x86) software actually uses our Highway library to run on whatever size vectors and instructions the CPU offers.

This works quite well in practice. As to leaving performance on the table, it seems RVV has some egregious performance differences/cliffs. For example, should we use vrgather (with what LMUL), or interesting workarounds such as widening+slide1, to implement a basic operation such as interleaving two vectors?