good train > plane > bad train

I regularly take the train between Moscow and Kazan. It's 12 hours, you can get on in the evening, have dinner on the train and then get a decent 8 hours of sleep before getting up, having some coffee and arriving.

It's much longer than the equivalent flight, but also much more comfortable. There's something annoying about airports - with the train I can get to the station 15-20 minutes before departure and it's fine.

Once the train rides get much longer than 12 hours it shifts, but there's a sweet spot right around there.

Correct, you weren’t riding a bullet train.

There are these really fast trains that exist in a dozen countries.

China has 30,000 miles of high-speed rail.

Well duh x) because the "train" is dogshit, that's exactly my point. If instead of a 28 lane highway there was a dirt road, or instead of an intl airport and jets there was a grassy field and biplanes, nobody would drive or fly respectively, either x)

? No, because (1) the distance is still short and (2) 2500km/h flight is uneconomical so it's never going to happen anyway.

Even if you don't, you have property owners whom you'll need to either convince to sell or you'll have to get eminent domain to cross their land. Across multiple jurisdictions depending on distance covered, any one of which could delay your project by months or years with procedural objections or hearings. You'll need environmental impact studies and accomodations for the entire route. And for high-speed rail you'll need to build underpasses/overpasses at every road crossing. And once you build a rail line you're pretty committed to that route. Air travel avoids all of that.