Zoning has always been about protecting those working 30 years to pay to live there; would you buy a nice new car if the government could switch it for a used Yugo whenever it is politically expedient? - and that would only be 5 years of much smaller payments at most thrown away/lost.
No zoning is about giving the government power over your property.
If they want they can change the zoning on a adjacent property with a vote.
Thus you lose any protection you thought you had.