I just looked up air fare. Seems like you can get a $27 ticket from la to las vegas. Takes about an hour and a half. That's always the real competitor with trains, even in europe where trains supposedly rule.
In practise the flight is much slower due to security etc, and having to get to and from the airport.
For example, I wouldn't consider taking a flight from Copenhagen to Århus (40 minutes vs 2¼ hrs) as the saving is wasted on waiting, and flying is much less comfortable.
(That's an extreme example for the distance, as it crosses a sea.)
It's certainly a competitor, but definitely not the preferred option.
In practise the flight is much slower due to security etc
Only for very specific routes. If I want go to from here to the one of the maybe 4 closest large cities, I'm definitely taking the train. If I want to to go from here to just about any other major city in Europe flying is almost always much faster. A bunch of people from work where going to a conference in Amsterdam a few years ago and some of them wanted to take the train for environmental reasons, and the train was literally 20+ hours door to door from the midsized European city I live in. Directly flights are under 2 hours.
Trains don't rule Europe on cost, airline prices are usually lower if you're willing to fly Ryanair or similar.
But the train is much faster if you want to go from city center to city center for a distance that's a relatively short flight. Like London to Paris or Amsterdam to Frankfurt. If you want to go across Europe from one side to the other, the plane is much faster.
There are a lot of indirect subsidies going into air travel. To me this has always seemed rather perverse, and the money should have been invested in proper rail infrastructure instead, from a climate standpoint as well as for convenience (a proper rail network deposits you in the middle of a city without the need for a car, you don't have endless security controls etc.).
That's not really a subsidy for air travel, in fact it's a cost. People here are talking about how they would prefer rail so that they don't need to go through security at the airport. That's bad for airlines.
For example, I wouldn't consider taking a flight from Copenhagen to Århus (40 minutes vs 2¼ hrs) as the saving is wasted on waiting, and flying is much less comfortable.
(That's an extreme example for the distance, as it crosses a sea.)
It's certainly a competitor, but definitely not the preferred option.