[quentindemetz]

Beijing to Shanghai is 1200km and and the high-speed link there seems to thrive just fine

[lovemenot]

I imagine it depends on the number and scale of existing intermediate cities. The proposed route in Australia passes through nothing of note.

[seanmcdirmid]

The Beijing to Shanghai HSR is direct. But the same tracks support other lines that stop at other cities along the way.

[robocat]

I suspect they never had to pay for the capital investment (because it was built or subsidised by the government).

[duckymcduckface]

Chinese aviation industry is special, a lot of their airspace is military and is closed to commercial aviation which leads to heavy congestion and thus late arrivals and not a lot of slots. Those high speed trains end up being workhorses for their transportation infrastructure.

[dagw]

A quick search seems to show that a high speed rail ticket is significantly cheaper than flying. Most high speed rail projects that have to, more or less, cover their own costs tend to cost about the same as flying.