It is strange how the phrase personal responsibility has gotten turned around. It use to be used in the context of 'this is my personal responsibility' now it is used to blame others as in 'it's your personal responsibility'. It is used to push any responsibility onto other people to allow themselves to avoid it all together. It all comes back to self indulgence and selfishness. People think 'why should I do this when I am not the one dying; it's their problem not mine. Why should I have to go without just to please someone else I don't even know. I am the most important person to me, as far as I am concerned, everyone else is a second class citizen'.
I don't think this attitude is constrained to the US but it does seem to have become magnified there lately . When people become increasingly selfish, others around them lose generosity, sympathy and empathy. In the end everyone gets infected with selfishness and sociopathic tendencies increase. I am glad I am not living in the US these days. Covid is not the only pandemic in the the US.