You are always going to have folks with buyer’s remorse — I expect that.
However, even besides the obvious frauds every one of these “buyer’s remorse” stories gets repeated and rebroadcast endlessly because it supports the narrative.
Then there are those who are not merely enthusiastic about the vaccine, but on a personal mission from God to wage war on the unbelievers who have not been vaccinated.
I think you hit it on the head “mission from God to wage war on at the unbelievers”...that is Leftism in a nutshell.