eSport viewership numbers are untrustworthy because the games incentivize players to tune in with special in game rewards.
Also for reference the last Superbowl was watched by 100M viewers.
Also for reference the last Superbowl was watched by 100M viewers.
Getting precise numbers for marquee sporting events is difficult, especially outside of the major US sports leagues, but the Super Bowl is on the shortlist for most-viewed single sporting event. Comparing only among US sports leagues, the Super Bowl has more viewers than the final game of the next several leagues combined--the next largest finals seems to have somewhere around 20M viewers.
By contrast, the smallest of the "big" US sports leagues can only manage around 5 million viewers for its final games.
The cost of in-game rewards is in most cases marginally zero in software.
It’s not until super recently that other brands have been going into esports advertising. Those newer brands, sure I can see them being lured by high viewer counts. But as an example, you can see the sponsors list in this page for the World Cyber Games 2005 https://en.m.wikipedia.org/wiki/World_Cyber_Games_2005
Samsung, Intel, Razer, etc.