The problem with Demos is they eat into Dev time, deciding what to include, making sure if doesn't run like **** which will instantly turn people off who might have bought or pre-ordered anyway. Deadlines are so tight with absolutely hard release dates that even delays of a month in the case of Survivor likely had to be signed off by the board or CFO at the very least. AAA games are no longer fully in the hands of the developers, the Studio and upper management are all in there, meddling and 'making suggestions'.
The bigger a developer gets the more involved non-gamers become, especially at board level and in senior management. You get hires coming in from big banks, petrochemical companies and all sorts who likely would say the last game they played was Snake on their Nokia 3210, but they're successful businessmen so get hired and then start making decisions for profit or bottom line and expect every game to have paid for DLC or Cosmetics to continue to bring in revenue after launch and initial sales.