That's a high single-event number. Do the numbers sustain across the year? MLB and NBA have over 100 events per year (considering all the days games as one daily "event")
While some people stay with a game/genre/gaming forever I notice a lot of people "age out" and can't even invest the time to keep up with watching esports (much less playing the games they're watching). I wonder if, assuming my observation is the norm, that will impact numbers as society has less children.
People age out but those that age out don't have the attitude of "old people", which in this case is "why would people watch this" and "this is a waste of time". (not trying to generalize older people but i think you guys know what type of people I'm talking about) Slowly esports and will become more and more mainstream (probably not completely mainstream but I can't predict the future) and more and more people will watch it.
Also, for the people that age out it seems like 3 more people join. Search viewership growth for games like League of Legends, Dota2, and CSGO and you will see that watching videogames is serious business.
Mm, League has events maybe 20 or so weeks of the year (matches mainly on weekends), for probably 8 of those we see very high numbers. But Twitch also hosts other stuff - SC2, Hearthstone, and CS:GO also draw large crowds. Dota 2 also, but Valve does have their own streaming platform for that.