I feel like 16-bit MCs aren't popular because they aren't popular. They offer a straight-up 2x performance increase in most applications and something like a 4

I feel like 16-bit MCs aren't popular because they aren't popular. They offer a straight-up 2x performance increase in most applications and something like a 4-10x performance increase with 32-bit numbers (not to mention the space savings from fewer instructions). Despite this, the 16-bit MCs all seem to be rather niche. I'd love for an open RISC-V variant that could fill this gap and allow sourcing of the same ISA from multiple companies.