Arguably the largest demand for consumer bandwidth over the first decade of the Web's existence was porn. From about 1996 forward (Quake), gaming has also helped move the needle.

These days sites like Xvideos, Pornhub etc are monsters when it comes to bandwidth consumption, and there are dozens of major streaming porn sites.

That constant bandwidth demand has been a great catalyst in terms of encouraging ever faster speeds.

How much content is on sites like YouTube or Dailymotion related to sex appeal?

Facebook had intentionally built-in sex appeal aspects to it. It was for college students after all.

Snapchat? Chat roulette? MyFreeCams & Live Jasmin (both of which generate tens of millions in sales)? There are many porn related sites in the top 1,000 global sites. Titillation moves things forward and always will. Humans are sexual beings.