You're thinking of a different voting method, but the answer is that you have to be an organizing member of the change you want to see. When Fargo switched to approval it was because a single person decided "fuck it, I'm gonna make this happen." They built a team of volunteers and forced through a referendum, and ran a campaign to advertise and support it.

We're advocating to take away power from those who have it. They will never allow it voluntarily, you have to make it happen.