Just because some authorities implement it poorly doesn’t mean it can’t be effective. i just looked up new york rent control and it says

To qualify for rent control, a tenant must have been continuously living in an apartment since July 1, 1971, or be a qualifying family member who succeeded to such tenancy. When vacant, a rent-controlled unit becomes “rent stabilized”, except in buildings with fewer than six units, where it is usually decontrolled. In units within single and two-family homes, the tenant must have resided in the unit continuously since March 31, 1952, to qualify for rent control. Once the unit becomes vacant, it is decontrolled.[4][5] Rent control does not generally apply to units built after 1947. wikipedia

well then what is the fucking point? and rent stabilisation seems no better