I trust that your question was rhetorical, and designed to make us consider what delusions we are living under today. OK – I’ll take a bite!
Some enormously popular delusions today include the numerous stripes of nationalism, religion, and the belief that capitalism can ever bring peace and prosperity to all. Fashion and arguably clothes themselves are designed above all to delude. Politics seems definable as the art of mass delusion, most definitely including American-style “democracy.” …And then there are innumerable little mass delusions, such as the perceived need to wash your body with soap every day.
The world of health and medicine are popularly colored by defeatist deathism, but might actually be an oasis of rationality when you look at other parts of the present human condition. Still, given widespread addiction to prescribed “meds” and various other shameful realities, perhaps one big delusion is our faith in the suffix “MD.” Haha.
Hey, this is fun! …But where does it lead? By and large, people are happy with their illusions, and do not want them challenged. Historically, we cling tightly to the dominant illusions, even when they are widely known to be factually questionable, until there is a crisis which forces their unmasking and abandonment. …But even then, when the crisis passes, we quickly return to dogma. I don’t believe that most participants in mass movements even believe what they are doing is right, but rather are driven by the desire to be on the winning team. In such gutless pursuit, reason and tolerance are set aside as a precondition of membership.