This sounds like a reference to the Great Firewall of China. (Though, on second thought, the GFW disrupts much more than 5%.)

There's two parts, I believe. One is the outright blocking of certain websites. The other is the throttling of every foreign website because the exchange points coming in/out of china are always congested. If both netflix and comcast's streaming service are similar in price and catalog, but netflix is always buffering because comcast is throttling netflix (intentionally or otherwise), then you might be inclined to go with comcast just for less hassle.

Or because the average person is more likely to blame Netflix than Comcast in that scenario.