> , but the vast majority of their initial development was government funded
Source?? Most countries developed railroads with private investments first.
If you were to talk in terms of asset value, then yes, the government did fund most of it; but that was because the Shinkansen were enormously expensive compared to the old, narrow curvy mainline network. In fact, the large Shinkansen debts are why JNR had to be privatized; the government restructured the private groups so that all the debt was confined to a ‘bad bank’ paid for by the government.
People seem to think nowadays that all the infrastructure we have has sprung out of thin air by pure goverment will or something.
The Saikyo, Keiyo, and Musashino Lines in Tokyo were all built by JNR. So was all the Shinkansen. And all the main lines around Tokyo were quadrupled or sextupled by JNR at great cost. And let’s not forget the feats of the Kanmon tunnel to Kyushu, the Seikan tunnel to Hokkaido, and the Great Seto Bridge to Shikoku.
Tokyo Metro and Toei are also state-owned, and private operators directly benefit from the through operations into the Yamanote loop.