telcos .... dumb bit carriers..
What else can they be? They carry customer voice, SMS and internet data and it's up to the customers what 'value' they place on the conversations and the data that is transferred - with the OTT players helping the customers independently of any telco input to the value-added process.
If the telcos want a slice of the pie, they will have to create a service or value-added 'thing' that customers are willing to pay for. They can of course block VOIP and whatever detectable activity they like, but if they do that then it will lead to a backlash and legislation against them.
Google, Facebook, Twitter, etc, have had years to create and develop their value-added 'thing' and are well established with enourmous user-bases. What could the telcos provide, even if they tried?