There'll be no new third rail electrification, though (apart from some minor infill, or reorganisation around depots).

The conversion of remaining mainlines to 25 kV overhead AC is going slower than anyone wants, but already over 70% of passenger rail journeys use electric traction (and actually more like 80% by passenger kilometers).

There are an awful lot of low-traffic rural lines that it won't be economic to electrify using current technology, so we'll need to rely on battery electric for those.

Either way, it's largely orthogonal to the problem of electrifying road transport.

Oh, right, I completely forgot about those! To be fair, there are reasons everyone else usually sticks to overhead lines outside of subway systems.