If ticket sales decline, and networks back out of broadcast rights, we will see team values decline, and NFL teams sell for lower prices.
And we will have a good indication of that view when taxpayers of a city refuse to fund an NFL stadium.
But for now, taxpayers usually vote for stadium deals.
You are correct. Taxpayers usually vote for stadium deals.
However, I will take this opportunity to proudly point out that the voters of the City of San Diego rejected taxpayer funding of a new stadium for the Chargers in November 2016. The Chargers then moved to Los Angeles in 2017.