> This pattern does not seem to be driven by changes in word meaning, publishing and writing standards, or the Google Books sample
To say "social science studies are bullshit" implies a more generalized claim to me than "social science studies are always bullshit"
People use overt generalization words like these, in my experience, to indicate generalization with obvious exception.
This study is selecting for precisely the wrong thing, imo, or is not properly interpreting what they've selected.