The article doesn't actually offer any evidence, apart from the fact that Netflix has doubled its subscribers.
The only problem is that there are still a few shows we really want to see (like Game Of Thrones) that we can't find a way to legally acquire. Without cable there is no HBO.
I bet more and more people are going to be turning to piracy to get the content they want when they cut that cable cord.
Compare to claims that piracy decreases sales.