You know, I've expressed the same idea over the years in different forums and I always get someone who responds like the person above did and it has always baff

You know, I've expressed the same idea over the years in different forums and I always get someone who responds like the person above did and it has always baffled me. Then COVID happened and people who reticently got the vaccine and then had mild covid said "COVID was no big deal, I hardly felt anything" while conveniently ignoring the fact that the vaccine did something. What is the name of this cognitive bias or fallacy? It's everywhere.