Aviation is highly taxed (about half of your ticket). Subsidies (or more accurately tax discounts) are only on fuel which is something like 10% of your flight costs. Rest goes on staff and capex.
There already is form of transport that's much cheaper than train or flying which is called BUS. We can make them fully electric and even have different classes. They can share existing infrastructure that doesn't require thousands of specialised people to maintain or operate...
>They can share existing infrastructure that doesn't require thousands of specialised people to maintain or operate...
Spending on highways and roads was $175 billion in the US in 2016 [0]. They absolutely do require massive numbers of people to maintain them - for example, Caltrans, the California agency that manages the state highway system, has over 18,000 permanent staff.
