the dream of "millions more streaming online" is just a dream
It's reality, not a dream, and has been for a while. It's hard to find numbers to put this into perspective but I found some info from IEM San Jose (december 2014) and DOTA2. IEM had 4 milion live viewers during a two day event. DOTA2 reached 2 million simultaneous viewers with a total of 20 million viewers. While NCAA is bigger than both events combined the numbers are not that far off either. NCAA is an old organisation with a 50 year television history that has a lot of resources to promote it's events. As eSports have time and demography on their side I expect that eSport will continue to grow. Especially now television broadcasters are starting to pick it up.
The mass appeal of watching someone play video games is just not there.
That statement makes me wonder if you've actually watched eSport. In my mind it's no different than watching people play baseball or tennis.