In five years the spread will be dead. It will rest at the bottom of Lake Ichigumi with the K-Gun, the original shotty, the run and shoot, the wing-t, and certain west coast concepts. It's not difficult to anticipate this trend, and the league is already shifting. Spread is speed and space. Defenses adjust to disrupt the timing and get into quick pursuit angles. Offenses will eventually get beat by these upfield/penetration, and realize what Joe Gibbs did two decades ago. Block the defenders and they are at your mercy. So, like in anything else, the balance shifts back towards blocking and physical football. Not too difficult to grasp, and certainly nothing brilliant, but far too often
media is well behind the trend.
As Patchick pointed out, it's not a demand conversation but a supply conversation. Don't get me wrong- there are some great tight ends that are coming out. However, a guy like Gronkowski is much more of a true TE than Hernandez or Jimmy Graham. There will be excellent opportunities to utilize their skill sets, but the position and the game as a whole will always seek it's own level. Those who become enamored with the offense will be out thought, out strategized, and eventually become obsolete. Those that can take the concepts with validity each new trend brings can anticipate the shifts, and grow mentally.
They're getting tougher, more physical on offense. They recognize this trend. Now bring me my fullback!