This might already be true in some markets and it continues to develop. Some TV broadcasters have already reacted to this (ie. ABC, YLE) by creating their own streamed offering.
Interesting thing here is, what happens to the money spend on TV advertisements? There are no more so many minutes of spare time, that people would consume watching commercial breaks. You could try to add commercial breaks into streamed content too, but user adoption of that might be difficult to achieve.
For example there was a projection that TV-advertising will continue to grow from 65B (2012) to 72B (2016) in US market. My question is why it would grow if people are moving more towards new way of consuming streamed content. I would expect to see heavier shift towards online advertising here.