Were FRAM destroyers really frigates?

Should US Navy FRAM destroyers be categorized as frigates, and what roles did they perform beyond close-range anti-aircraft work and gun fighting?

They remained destroyers by lineage and contemporary service, although their anti-submarine optimization anticipated later US frigates. Doctrine, capability, and national terminology increasingly blurred the distinction.

Second World War frigates were designed partly for mercantile-style construction, while later purpose-built frigates emphasized anti-submarine warfare. FRAM-rebuilt US ships remained low-end destroyers in lineage and contemporary service even as their missions increasingly resembled those of frigates. They also retained more surface and air firepower than some Royal Navy Type 15 and Type 16 conversions, which adapted destroyer hulls for the same fast-submarine threat. Gearing and Allen M. Sumner conversions began with larger hulls than the British War Emergency designs, while the Fletcher comparison is closer. Hull size, Atlantic and Pacific operating requirements, service categories, and national terminology explain why a shared role produces different classifications.