There's only one reason Tubes do well. They're free and in 2016, the only sites that are at the top are free ones. Be they Google, YT, FB or whatever the consumer demands free and will not pay for anything unless they have to.
Even webcams are free.
The solution is to move to a model that uses free and sell the ad space. It started 15 years ago with TGP sites where if 1-100 clicks on a TGP actually ended in a sale everyone thought they had a result. Now it's 1-50,000 getting another 1,000 to look at something they have no intention of paying for is fast becoming pointless.
Getting traffic is easy. The job is to keep it coming back day after day. Retention is the #1.
And that can only be achieved with content. Yes you heard it from me first.
Content is king.