Eli Manning of the New York Giants calls a play against the Detroit Lions during their game at MetLife Stadium on September 18, 2017 Abbie Parr/Getty Images

The NFL has long been the cornerstone of the U.S. pay television market. Viewers’ loyalty to their favorite teams and the tradition of watching games on Sunday afternoons (and Monday nights) provided stability and certainty for stakeholders across the TV ecosystem.

Mass-market advertisers could plan fall marketing campaigns knowing that NFL games would reach just about everyone. Broadcasters and cable channels (such as ESPN) could enter into long-term deals for broadcast rights knowing that people would “always” want to watch football, creating an anchor tenant for the rest of their programming lineup. Last but not least, pay TV providers have long used their exclusive distribution rights to NFL games as both a carrot (to attract new subscribers as DirecTV did with its wildly successful Sunday Ticket package in the 1990s) and a stick (to keep existing households from canceling service regardless of the cost or frustration many folks have with their pay TV provider).

The question today, however, is what if this entire edifice is just a house of cards? NFL ratings have fallen significantly across all providers over the past seasons and so far 2017 is not looking any better. The only positive element to that decline may be that fewer people have to watch the sad sight of the Los Angeles Rams playing in front of a mostly empty stadium at the Coliseum. There are endless theories about the decline, from the rising popularity of video games to player safety to (ridiculously) the Colin Kaepernick situation.

My own view is that declining NFL ratings are the logical outgrowth of the decline in legacy linear television overall. This larger decline has been going on for over a decade now; is rooted in a fundamental shift to anytime, anywhere viewing on broadband devices; and affects all legacy TV programming to one degree or another. In short, contrary to the hopes (or delusions) of some in the TV industry, the NFL is not immune to these larger societal and viewing dynamics.

The more important question is: What happens to the pay TV edifice when the NFL cornerstone isn’t there anymore? The answers are multiple, but two are particularly important.

First, the link between household growth and pay TV growth has been irreparably broken. The creation of a new household—most commonly by a young adult leaving home—used to almost automatically result in an additional pay TV household. That is simply no longer the case. Millions of American households are living happily without pay TV and one of the reasons is that Monday Night Football and other NFL games are simply no longer must-see TV. Put another way, U.S. legacy pay TV households have peaked and will only decline going forward.

The second effect of declining NFL ratings is the slow collapse of the supersize pay TV bundle itself. If the NFL isn’t must-have content, then nothing is must-have content. The result is a mushrooming of skinny bundles from providers as varied as Sling TV, DirecTV Now, PlayStation Vue, YouTube TV, and Hulu’s Live TV.

These services vary pretty dramatically, seemingly agreeing only on three things: people want cheaper pay TV offerings; what people want varies (including access to the NFL); and half a loaf (in terms of monthly subscription fees) is a whole lot better than none.