I liked the article, but I was bothered throughout by the word "bullshittery". Why add the "ery"? "Bullshit" is already a mass noun, and the standard slang use

I liked the article, but I was bothered throughout by the word "bullshittery". Why add the "ery"? "Bullshit" is already a mass noun, and the standard slang use of it fits fine everywhere he uses his unnecessarily longer term.