Bus Lane? Try Ford Lane.
What Ofcom seem to be missing is that if you're streaming your content from one your Broadband Provider's "approved suppliers" (ie themselves or one they get a kick-back from) then your traffic is prioritised over someone who is streaming from a non-approved supplier.
This is the equivalent of having a "Ford Cars Only" lane on the motorway because Ford have struck a deal with the DfT to charge their customers a fee to use that lane and pay the DfT a percentage. Other cars aren't allowed to use that lane because their manufacturers aren't paying the Government for the privilege.