I don't think soccer will surpass tackle football or basketball. If concussions makes tackle football lose a lot of popularity, maybe it could surpass that as well, but I don't think that will happen. I think soccer is the third most popular sport in the USA, but I think it has a long way to go before its close to tackle football or basketball.
In recent years, I'm not as much of a baseball, basketball or tackle football fan. I do watch some important playoff games, some important college games, select regular season games at times, but I'm rarely excited to watch those sports. The exceptions are that I'm a Jets and Mets fan, so I will watch both those teams, and I'm really excited to watch those two teams play, but the average baseball, basketball or tackle football game is just not something that I am really interested in watching most of the time.
I could watch just about any hockey game, soccer game or golf tournament. Those are my three favorite viewing sports in recent years. It helps that I have favorite teams and athletes in those sports, but those sports are much more interesting to me even when I don't really care who wins.