The investment needed goes way beyond that, our railways are among the most well utilised in Europe
(source) , but our biggest problems are capacity and mixing of slow local trains and fast express trains on the same lines, and have hamstrung ourselves with ridiculous controls preventing, interfering and inflating any attempted infrastructure investment (See HS2 and any attempt to build new roads or power stations)
The problem isn't just short term populism in government, its that most of the people in the UK have no vision.
