One reason for the change is that because of the mass appeal and coverage of radio and movies, "they became simpler". They had to simplify in order for everyone to get it, to relate to it, and to enjoy it, instead of, like books, appealing to "a few people here, there, everywhere." Eventually, because people were busy and not wanting to take the time to read, every story was condensed to "a one-page digest in a book." That way, everyone could know what the story was about without actually reading it. One result of shortening the books is to shorten everything else down, to quicken its pace also: "School is shortened, disciplined relaxed...languages dropped, English and spelling gradually relaxed...Life is immediate...why learn anything?"
The other way the culture became a "crowd pleaser" is through the editing of content so that no one became offended. Books sometimes offended people, stirred them up, caused unrest and unhappiness, and Beatty says that "we can't have our minorities upset and stirred...People want to be happy." So, shorten things up, monitor the content, and you are supposed to have a content, smoothly operating society, right? Considering the amount of warfare that exists in Montag's society, it seems they might be looking in the wrong places for peace and happiness.