Maybe, in the past stupid was mainly reserved for people who knew very few facts. Knowing or having access to facts was much less common before the internet. So people used to argue about facts. But since those arguments were about facts, they always died down (someone was right and someone wrong) and you did not have a feeling of "expanding stupidity".
Since access to facts is pretty much universal now, people have started arguing about values. If someone states they have different values than you, you call them stupid. Since no one is right an no one wrong, the arguments don't die down and you perceive expanding stupidity.
Stupidity is about lacking intellectual capacity (not necessary the same as IQ, also things like not being interested in thinking, or lacking necessary facts about a subject can give you a lack of capacity.)
Both stating wrong facts and having ridiculous values is correlated with being stupid. So I do not really see how the Fact-value distinction can be used here, stupid people fail at both.
(https://en.wikipedia.org/wiki/Fact-value_distinction)
Maybe, in the past stupid was mainly reserved for people who knew very few facts. Knowing or having access to facts was much less common before the internet. So people used to argue about facts. But since those arguments were about facts, they always died down (someone was right and someone wrong) and you did not have a feeling of "expanding stupidity".
Since access to facts is pretty much universal now, people have started arguing about values. If someone states they have different values than you, you call them stupid. Since no one is right an no one wrong, the arguments don't die down and you perceive expanding stupidity.