6809 is a better exemplar, but, yeah, we knew this stuff way back when.

The problem is that everybody around RISC-V wants to sell IP instead of a chip. Most of the worst brain damage follows from that.

The rest of the brain damage follows from "We want to compete with ARM A-Series cores." No. Just ... no. Nobody willing to spend that much on a processor gives one iota of damn about ARM licensing fees.

So, the semiconductor market wants a cheap, consistent chip that operates in the deep embedded space while the RISC-V ecosystem considers the mere thought of that to be icky beyond reason. And China will push on this like Longsoon and pray that somebody figures out how to make it not suck (Prediction: they won't succeed.)

And, the worst part is that RISC-V has basically lost its window. The single possible advantage that RISC-V had was that as people converged to a shared tooling ecosystem it would create lockout. Unfortunately, that convergence never happened so, at best, we got some shared compilers. And, now, AIs can basically one shot all your other tools around it and probably the compiler not far behind. And there goes your ecosystem lockout.