i once heard that the tone/cadence/style that we hear in older movies (40s and 50s roughly) was actually learned by actors and not actually reflective of how Americans spoke at the time. I think it had a particular name as well. Is that true? And if so, what was the cause of its implementation? Did actors put it on their resume as a skill or was it assumed at a certain of acting? When did it stop being the popular style?