Obviously a large reason for that is on field product, but sports is evolving away from being an up close and personal affair.
Going to the stadiums used to be the only way to see the game and experience the fan fare, packing the family up and making the trek also used to be one of the few things to do.
We have to understand generational differences when looking at changes and/or shifts in things such as a significant drop in season tickets and attendance.
Gen Y and the Millennials are not as interested in season tickets. For several reasons. One reason is that they simply have more options of things to do on the weekends than their parents and grandparents had. They may be interested in buying single game tickets a couple of times a year if things are going well, but they are a more mobile, exploratory, and able to do countless other things.
Another reason is that younger people are growing up in a discount era, and there is nothing cheap about going to a single game let alone 8 of them, and for the younger people who do love football and want to spend their time and money watching it they can stay at home and go to a friends house or a sports bar and watch a half dozen football games on big screens for less money than a single game ticket.
Thirdly, university enrollment. Back in the day campus was packed with kids from the state and from near by areas who more often than not had ties to the university. Kentucky kids grew up UK fans in UK families. Then they went to UK themselves, graduated, stayed home and raised UK fans themselves.
Nowadays, UK has 30,000 kids and 12,000 are from everywhere else. Same goes for all other colleges. Kids from California, Texas, Canada, Vietnam, Europe, Africa, etc don't give a hoot about UK athletics, at least not long term. They'll all go games here and there but they'll graduate, leave the state and go have families elsewhere. Kids from Kentucky will go to Ohio, Florida, New York, Kansas, etc meet somebody from Missouri, Oklahoma, Washington, etc, graduate move to Mobile and raise a tide fan.
If you want an indicator of how and where things are going just pay attention to the student section, the future alumni and season ticket/single game buying base. They'll show up late and don't stay for the whole game, a lot wont make it til half time. Some of the more loyal of them will last til the 3rd quarter. It may fill up and stay full a couple times a season for a big conference game and UL if things start off well enough.