maybe Kerry or others in the Dem party leaking these,because Biden would be by far the “best” candidate (from our perspective) to run against President Trump, so the Dems gotta keep upping the pressure on Biden to drop out ...
of course, the Pubs could be leaking too to weaken Biden and force the Dems to deal with him, thereby creating chaos in the Dem party ...
hell, even the russians could be leaking to force the Dems to get a stronger candidate to run against President Trump ...
We know who leaked the phone calls, there is no need for speculation.