They will say it was the masks and the distancing. Their problem is that areas with and without mask mandates have the same infection rates. It was the distancing of sick people that made the difference: Until 2019 it was just normal to have people sneezing in public transportation and workplaces. Sick people were seen as working class heroes when they showed up at the workplace coughing and sneezing. This will never be part of our culture again.