Far from it: NR has engaged and Mark Carne has personally promised that his company intends to install replacement OLE, subject to the inevitable caveats about funding (which you'd get in any public works project). Contractors have already been commissioned to design the equipment and consult on the environmental impact.
My emphasis above is what the the Goring Gap campaign are hearing.
The paragraph from his letter actually says (again, my emphasis):
I also re-affirm that should the outcome of the design options and the public consultation highlight that Network Rail should undertake retrospective works to alter or replace the installed apparatus, Network Rail intends to undertake such works as are necessary subject to costs and the agreement of funding. The entire project is paid for wholly by public funds so we have a duty to minimize the costs to Government and the taxpayer whilst delivering the economic and environmental benefits that an electric train service will bring.
Quote 1 != Quote 2 (substitute "<>" or "ne" for "!=" as you prefer)