Because they have been talking about this for years and are still no further forward.
I agree with Ox4Eva shocker (almost!)
I’ve lost count of the number of grandiose plans to improve Oxford’s transport. Few ever materialise - but there is some scope with this one.
The infrastructure is already there so the construction is fairly easy (although the legal wrangling would be tricky) and since the most competent franchise Chiltern are involved, it can be done and to a good standard.
Whilst 2019 would be incredibly optimistic, there is hope for this being a reality. Let’s face it, for home and away fans being able to reach the Kassam by train without the need for that tedious bus journey, it could open the club up for bigger crowds.