Most cost-cutters get an antenna, especially if they have any interest in the NFL (and if they don't it's a moot point for what we're talking about).  

With the exception of ESPN, cable doesn't get you any more games than the OTA channels get you.  Even the NFL Network games are simulcast on a local channel (typically CBS, like tomorrow night's game).

To see any other games, you had to purchase the (expensive) NFL Sunday Ticket from DirecTV.  Virtually anyone THAT dedicated to watching NFL games isn't gonna cut the cord.  

And I did address the rest of your list in a collective way... those were all things that had been happening in 2015, 2014, etc as well, yet ratings continued to do very well.  The dramatic reversal came at the exact time the anthem protests started (the start of the 2016 season).