This is old media thinking writ large. People pay for products - Tivo, DVRs, iPods, TV series DVDs - that turn streams into files they can watch when they want to.
We've solved how to send video over the net many times already.
The rare cases where millions of people want to watch the same thing at once — Presidential Inaugurations or faux Gladiatorial contests like American Idol, the World Cup Final or the Superbowl — are great uses for broadcast TV or satellite, and lousy uses of the net. What works is watching the event with friends on IRC or Twitter or a social network, sharing comments. That's what you need to stream over the net with low latency.
Cuban is conveying the last gasp of the self-important TV broadcast mentality that dreams of intoning "here we are, live to the nation", and all we can do is listen. But we can all talk back in parallel now, and build our own narratives with our own publics. That's what the net is for. As Douglas Adams put it last century:
I expect that history will show ‘normal’ mainstream twentieth century media to be the aberration in all this.
‘Please, miss, you mean they could only just sit there and watch? They couldn’t do anything? Didn’t everybody feel terribly isolated or alienated or ignored?’
‘Yes, child, that’s why they all went mad. Before the Restoration.’
‘What was the Restoration again, please, miss?’
‘The end of the twentieth century, child. When we started to get interactivity back.’