As a whole? Yes. Although I don't think any one game will be as popular as any one of the main popular sports (football, American football, basketball, hockey, etc.) because the #1 game in any particular genre changes constantly and with each change new people enter the scene and older fans exit. If you look at FPSes for instance, it was CoD for a long time, then Overwatch for a few years, and now Fortnite. Now, of course, Overwatch and CoD are still popular but my point is that there are too many games that are similar that are fighting for viewership. You don't really have that in sports and hell, sometimes different sports that people are interested in aren't even in season when others are.
So do I think a Fortnite tournament will ever get the viewership of the Super Bowl or World Cup? No. Do I think the viewership of the first person shooter genre in general might? Maybe.