Stop blaming and shaming airlines on social media for full flights. I guess I’m shocked that people are shocked there would be others sitting near them on a plane. Why would anyone think the airline was selling them a ticket but not selling tickets to other people?
Ultimately if you do not feel it is safe to fly, then do not fly. If you do fly, wear a mask (whether the government is requiring it or not). Bring hand sanitizer – the TSA has relaxed carry on liquid rules for this purpose. And wash your hands.