If these are the complete facts and the rationale for the regulation, it falls under both the U.S. Const'n and the California Const'n, which may afford stronger rights than the federal constn. Zoning for neutral purposes is allowed if it is rational. The rule is neither rational nor neutral. It strikes at the very core of why this nation was created. I am certain the proponents of the bill do not expect to be upheld. Rather, they will bask in local glory, get votes and funding and scream foul at the court intervention.
In the United States, cities, towns are low on the totem pole. They only have whatever powers they were given from the state. Home Rule. They cannot pass laws with the same abandon as states or the federal government.
I do wonder what politician finds it meet to declare three people a church. California law determines what a church is, not a lowly creature of California's largesse. Neutral zoning is allowed. It must be rational. There is no rationale present here, save persecuting religion.
Someone needs to be recalled.