Why can't just the ones afraid of the virus do that
Because like everyone else, you're missing the point OR refusing to acknowledge it.
Masks are worn primarily to protect others, not yourself!! So by not wearing one, you are not making a personal statement of your 'freedom', you're saying 'fuck you Jack, I'm ok'!
Sovereignty over my body? You're being asked to wear a mask when you're in public, not being asked to chop your hand off!!
You are missing the point. Do some research and see that masks are almost useless in protecting you from the virus. And yeah I do have that attitude that you mentioned about and it's my right to have. Of course nobody is chopping anyone's hand, but once you get the whole picture and connect the dots you'll see why this masks narrative makes sense.