I disagree.
1) As much I like to blame millennials, it's not the younger generation who plays the lame card at games. It's the 30 to 50 year olds. The younger generation were the only fun crowd last night. Sitting at my tailgate and the bands playing the fight song and everyone sitting around me was acting like the band was interrupting their tailgate. Like WTF. No one is singing. No one is cheering... then inside the game 90% of my section left in the middle of the 4th quarter when we were up 14. The game was obviously not over. And these were mostly all non-millennials that left. That didn't cheer.
2) stating it's due to not winning titles is BS. I live in SEC country. I've been to tailgates at South Carolina, Tennessee, and Arkansas. They havent won crap in a long time either. SC & Arkansas never really have. Their games are still loud. They still cheer Rocky Top & Woo pig sooie. And loud. Go to Arkansas, basically anywhere and just say woo pig & random people will recall sooie. Same in eastern Tennessee, just say 'good ole rocky top', you'll get a response of "rocky top Tennessee"...
Blame the millennials. Blame losing. My view is it's the gen X who grew up spoiled are too busy thinking of what was and not just freaking enjoying the moment.