Zoning is NOT land-use. Here is the difference:
For example, if someone wants to build a subdivision on land designated agriculture, they must first change the land-use from agriculture to residential. At a later hearing, the land will be zoned for specific residential, such as apartments. Each land-use category can encompass many zoning types, changing the land use does not change the zoning. The zoning application is usually associated with a site plan and more details of the project. This does not go to Department of Community Affairs. There would NOT be a vote on zoning with Amendment 4.
Only people living in a municipality will vote on that municipal's plan. An application in unincorporated county will be voted on by the whole county as the unincorporated area is considered part of the county. That is a downside for unincorporated people, especially for a county as big as Miami Dade. Yes people in unincorporated North Dade would be voting on a land-use change in unincorporated South Dade (Like the UDB applications) but neither would vote on land-use changes in Pinecrest (which is incorporated -- Oh the joys of being incorporated). Pinecrest would not vote on a land use change in Palmetto Bay.
There are certain functions over which the county maintains jurisdiction, DERM, airports, waste, roads, water/sewer etc. Mostly these are issues that effect the whole county and have public safety/welfare components. I assume a land-use change in one of these would go to a county-wide vote even if it is located in a municipality. I doubt this would be a huge number of applications.
To put it in perspective: How many CDMP applications make it to DCA from unincorporated Dade in a year? 8 or 10? How many will go to DCA if they have to face a vote of the people? Maybe half that? Not that much to vote on to be sure!
Don't believe the hype from the folks against Amendment 4, the developers, the chamber and offending government officials. They want you to believe you will be voting on everything. Won't happen.