Well the juggernaut hasn't happened just yet, so it's not like anybody has to worry, really
Passenger-rail travel, and especially the newfangled-high-speed variety, of course
is a very politically broad-based endeavour, just because of the --generally publicly-funded-- rail infrastructure and upkeep investments required. It's not such a surprise, no matter how much window-dressing gets put on, like in the States and Canada, for the operating companies to be profitable or even public companies.
It's just part of life though, the air-travel industry has huge capitalisation too, just not anything fixed and tied down to the physical laneways, so way more configurable that way, and suitable for a truer competitive business environment among the companies participating. Doesn't mean that one's inherently more preferable to another, especially given the apple-and-oranges difficulty in making the comparison, but just that both are realities and will continue to evolve. Even if one gets displaced a bit at the expense of the other, for certain overlapping service niches.
Rail travel's still a tough sell in the States, especially with the fits and starts Amtrak still has to work with (and unrealistic Congressional expectations of 'showing profitability'). But this isn't anything etched in stone, and as needs, priorities and even political realities change, so too might the nature of rail transportation in the country.
In practical terms I figure the Northeast corridor will
see more high-speed rail service this decade, even without big rail infrastructure upgrades attached. Next decade after that though, seems to me there'll be a lot of that going on, and not just in the Northeast either, but those other zones mentioned as well. Even Florida, Texas and Southern California'll probably get their own within-state networks for up-to-date rail service, in the next twenty or thirty years.
So of course down the road, travelers in those areas and especially for trips 500 miles or less, are going to have a lot more options to choose from. Just not immediately though.