Pandemic restrictions are falling away almost everywhere — except inside many of America’s nursing homes. Rules designed to protect the nation’s most vulnerable from COVID-19 are still being enforced despite widespread vaccination of residents, and plummeting infections and deaths. Frustration has set in as families around the country visit their dads this Father’s Day weekend. Family members say limited visitation, physical distancing and shutdowns make little sense at this stage of the pandemic, when the risk is relatively low. They say restrictions meant to keep older people safe are instead prolonging their isolation and accelerating their cognitive, emotional and physical decline.