This was probably more true a decade ago than it is now. Pirating shows isn't hard, but it's slightly less easy than watching Netflix, so it only matters if the shows on The Pirate Bay are enough better than the shows on whichever streaming service you have to be worth the inconvenience.

There are a lot of good shows on Netflix. Enough that people don't have time to watch even them -- especially now that the Internet is a thing and a lot of the time people used to spend watching TV is now spent watching YouTube or hanging out on Reddit or whatever.

So if you have Netflix and not HBO then you're several times more likely to have watched Stranger Things than Game of Thrones because it was easier to do it. And for the same reason, people don't subscribe to twelve different streaming services, because they don't even have time to watch all the shows on one of them. Which means there's now a lot more fragmentation in what people have watched.