Delusion definition[1]: an idiosyncratic belief or impression that is firmly maintained despite being contradicted by what is generally accepted as reality or rational argument, typically a symptom of mental disorder.
Note that GP chose to describe "filter bubble bias" which is a neutral observation, whereas P chose to describe GP's idea as "delusional" which carries the connotation of a mental disorder.
> the epitome of filter bubble bias.
> This is delusional.
Delusion definition[1]: an idiosyncratic belief or impression that is firmly maintained despite being contradicted by what is generally accepted as reality or rational argument, typically a symptom of mental disorder.
Note that GP chose to describe "filter bubble bias" which is a neutral observation, whereas P chose to describe GP's idea as "delusional" which carries the connotation of a mental disorder.
[1] https://en.wikipedia.org/wiki/Delusion