Netflix will stream their version of HD on a 5Mbs connection without issue. Most broadband connections are at least that. So I think the statement "unless you have superfast networking, you wouldn't be able to stream a moving (sic) in chunks in realtime while watching it" is inaccurate for many people.
A lot of people still can only get DSL in their area, and it's nowhere fast enough.
The average speed in the U.S. is 3.9, which is lower than the 5 you say is needed for Netflix.
I rest my case!