I see it as a variant of the 'hedonic treadmill'. So many scenes of extreme behavior, by 'bad guys' and 'good guys', have already been done in filmed/televised

I see it as a variant of the 'hedonic treadmill'. So many scenes of extreme behavior, by 'bad guys' and 'good guys', have already been done in filmed/televised entertainment, that audiences are habituated to all the usual situations and nastiness. New works must keep going more extreme, in both what happens and what's shown on-screen (as opposed to suggested), to hold attention.