> design-by-committee
I don't think it is about having committee, but rather having a spec. And I mean spec, not necessarily ISO standard. There should be a description of how specific features work, what is expected behavior, what is unexpected and should be treated as bug, and what is rationale behind specific decision.
Coincidentally people here hate specs as well, and that explains some things.
I know there is some work on Rust spec, but it doesn't seem to progress much.
AIUI, that is what the MIR formalization work is about, and it seems to be moving along fine. My impression is that covers essentially all the interesting parts of Rust worth specifying formally.