I ride the subway every workday from Manhattan to JFK. I am subject to multiple customer exposures/day who come from/fly to destinations all over the world. I wear a mask and wash my hands. So far no COVID for me after 4 tests. I think if you are healthy with no pre-existing conditions flying is safe enough. People are, in general, much more careful about COVID prevention at the airport and on board aircraft, than in their day to day lives. I think the biggest problem to int'l airlines is the situation of extensive border closures. Many Americans can't travel overseas even if they wanted to, as is the case for many other nationalities.