while having the "everyone else is a selfish asshole" mindset, is just psychologically untenable

Hard to draw any other conclusion

During the early part of the pandemic, everyone was saying "we're all in this together! Social distance, wear a mask, you're supposed to protect other people!" It was a great outpouring of support for collective action. It was wonderful.

But almost the minute the vaccines became available, people immediately shifted to saying, "oh, I'm safe from it, I don't need it. If you're vulnerable, I don't mind if you wear a mask but I am safe from it." Or "I already had it, so I don't mind."

While everyone felt they were in danger, it was a collective action problem that we all had to protect each other. As soon as people felt like they personally were safe from it, suddenly everyone else's health was their problem, don't tread on me.

The mask came off, literally.

I don't think people are inherently selfish, I just think we live in a poisonous, atomized and individualistic culture where thinking about others or taking steps to protect others at minor expense to yourself is just an alien concept to most people due to our upbringing.