I don't know about the NFL, but there are plenty of sports fans who don't like the way the modern game is played compared to the sport they grew up on. And plenty of older fans who have dinky memories about the way their sport used to be played.
Complaining about wrestling is nothing new. When I watch Crockett, I'm enamoured with the excellent wrestling, but the Observer was full of criticism at the time. The same is true of WCW. My favourite period for that promotion was the early 90s when they were in the doldrums, but I don't care, because when I look back on WCW I pick out the good stuff and don't particularly care about whether the promotion was a success. At some point in the future, people may do the same with the current WWE product, cherry picking the good stuff that Cena, Punk or Bryan produced without caring about the ongoing criticisms of the booking.
Wrestling is more of a creative pursuit than sports. Creativity dries up and folks burn out. A lot of people give up on television shows after a few seasons. I gave up on the comics I was obsessed with as a child. Folks stop listening to their favourite bands or the musical genre they were into. Throughout wrestling history, we've seen that promotions can only be super successful for short periods at a time. Compared to most other forms of entertainment, it's a wonder that wrestling is still chugging along. It should have disappeared at the end of the 80s. But it hasn't, instead it's passed a lot of us by. You'd have to be the hardest of the hardcore to watch the same promotion continuously for twenty or thirty years without dropping out at some point. Only men like Johnny Sorrow are capable of such feats.
Hey, even I had my period of time not watching wrestling. From mid 88 til 91 I barely watched and from 91 to 94 it was sporadic . Shit I didn't watch any in 89, lol.