ex-EGLL
You are absolutely correct for pure ATC information being passed. What folks like Portished and Speedbird-London (and a few notable others) allowed the long-haul community to do is communicate with their companies and among other things, get re-dispatched in mid-ocean.
It would take more typing than I'm up to to describe why that was such an essential service. I've sweated through my shirt more than once wondering if I needed to continue to my flight planned, as compared to my real, destination without their support. Think "required" fuel reserves for a 13 hour flight vice "required" fuel reserves to begin a 2 hour flight to a "new" destination.
Thanks for the support Speedbird-London