I’m not a huge sports guy, but I think it’s one of the few things that are a common cultural bond for the country. I loosely follow sports so I have something to talk about with other people in work settings or when people try to make small talk at a bar.
I think if sports & blockbuster movies went away, you might as well go ahead and dissolve the US into a bunch of smaller countries. I’m kind of for that anyway, but without those big cultural events I basically have nothing in common with, say, someone in Arkansas other than language and federal taxes. Arkansas felt more foreign to me than Portugal in many ways.