I actually read an article about how the main reason that Game of Thrones became the cultural phenomenon that it did is because it's a weekly show. Thus, when crazy shit goes down, people spent the entire week talking about it and questioning what will happen next. It's a water cooler show, and the weekly buzz ends up pressuring more people to watch it so they can take part in those discussions about the show.
And if you think about it, Netflix has had some hits, but nothing even close to the level of Game of Thrones. Like, Stranger Things is very popular, but it just doesn't have anywhere near the buzz that Thrones has.
That makes sense, too, as when a show like Stranger Things drops, everyone watches at a different pace, which makes it hard to talk about it. Game of Thrones, on the other hand, is the type of show most people watch live or shortly after, and so the next day everyone can talk about the same thing since they only had one episode to watch instead of a full season.