Definitely one of the contributing factors. si.com published a list of other possibilities....NFL ratings are indeed down on top of that, would be interested in seeing ratings the last 2-3 years compared to the usage of daily fantasy sites though. With those effectively squelched in many large markets for the time being I wonder what their effect on watcher enthusiasm is.
10. Concussions
9. The crackdown on celebrations
8. The Cubs playoff run
7. Daily fantasy sports bans
6. Officiating
5. Increases in (TV) competition and cord cutting
4. National anthem protests
3. Oversaturation
2. Lack of star-studded matchups
1. The presidential election
http://www.si.com/nfl/photo/2016/10/20/nfl-television-ratings-decline-causes