There must be millions of words written analyzing why (U.S.) Americans prefer gridiron football and baseball and most of the rest of the world prefers association football [i.e. soccer]. I don’t pretend to have an exhaustive explanation, but there is one feature I find interesting and possibly useful for explanation. In these two “American” sports, a team can be losing and then be winning without first having to tie. This is dramatic. Last-minute touchdowns and bottom-of-the-9th grand slams can mean a team that is losing can win in one fell swoop. In association football, however dramatic, a team that is losing cannot seize victory in one action. The steady level of anticipation in the match is high, whereas in American sports it swings from low to very high and back.
Americans’ sports preferences are not monolithic, of course. Hockey is popular (for some mysterious reason) with the same kind of scoring structure as association football, and basketball has a more “American” scoring structure but it’s much closer on the spectrum to association football. Nevertheless, the two most popular American sports have this dramatic feature built in.
Likewise, rugby is fairly popular in parts of the world, and it has the more dramatic scoring structure. But it’s still vastly eclipsed in worldwide popularity by association football.
Surely the American preference has roots in American culture and may in turn reinforce parts of American culture, but to get into that I’d be getting in over my head.