According to Chuck Klosterman in his book on 'The Nineties' more people watched an average episode of Seinfeld than watch the finale of Game of Thrones or The Sopranos.
About the only thing that remains for mass audiences is sport. Even there on demand replays of sports are changing things.
Also don't best selling records or streams or whatever actually indicate far less revenue and a far smaller share of what people are listening to than they used to ?
Yes yes tiger king, stranger things, etc. these things are popular.
In 1983 over 50% of the entire United States watched the last episode of MASH live as it aired on NBC. And people talked about it for 10+ years.