[webprofusion]

This is mainly using "stupidity" as a catch all term for mass disagreement/apathy (often motivated by bias, mixed with ignorance) in the face of facts, plus the lack of applied reasoning and empathy - simply not thinking, despite having the capacity or simply not caring because it doesn't affect you or align with your bias.

[M95D]

Did you actually read the article? It gives a clear unambiguous definition of what "stupid" is.