Well, I don't know, but I bet if you or I or anyone else, probably including George R.R. Martin, was asked a couple years before GoT came on the air if it would become this kind of cultural phenomenon, it would have seemed wildly unlikely. These sorts of things are pretty hard to predict. It's possible that there won't be anything else like GoT, but it's possible that something else will become the must-see thing everyone is suddenly talking about.

(Of course, there's no guarantee it will be on any premium streaming service, or indeed any streaming service at all. Or that it will even be video anything. Currently I'm sitting at a Starbucks listening to music that gave me a possible answer to your initial question: it's the soundtrack to "Hamilton.")