Yes, eSports are big today and they will become even bigger but they will never reach the same status as "real" sports. For me there is no real passion behind eSports or atleast not close to what you can witness in football matches or stuff like that.
An entire generation is born into using smartphones, internet, videogames immediately.
As time passes these people will understand the flow of these games more and more, just look how freaking popular they are. (looking at you, league, etc) So e-sports will gain even more popularity because there WILL be a breakthrough in this "not understanding what is going on" problem you mentioned.
At least that's what I think.
And why do people know a move like homerun is good?
Because it's popular among people and they know basic rules, because they are exposed to it often, everywhere.
See? In time e-sports will reach the other sports because of this tech generation factor.