https://en.wikipedia.org/wiki/Texas_Central_Railway
https://communityimpact.com/houston/tomball-magnolia/develop...
I agree with you that it's too little too late, but at least they're trying.
The main difference is that this planning is done much further in advance (although at least the UK is well behind in terms of rail capacity construction - the UK and the US have many similarities in terms of government incompetence).
Only place that is faster is China, but they work on a different scale.
Connecting Dallas, Houston, Austin, San Antonio, El Paso, will take at least a decade, more likely closer to 15 years. There is no real scenario where it happens faster.
From El Paso you push to Tucson, Phoenix, Albuquerque.
From Houston you go to New Orleans.
From Dallas you go to Oklahoma City.
Then if other cities are smart at all and pick up some confidence about what can be done, and at a reasonable cost, you then see eg St Louis, Louisville, Cincinnati, Indianapolis, Chicago all link up. And so on.
The model for the US will be regional high speed rail, rather than massive scale coast to coast approaches. Maybe eventually you get high speed interlinking between them.
Atlanta or Jacksonville to Mobile and on to New Orleans, which gets you to Texas via Houston.
El Paso to Tucson/Phoenix gets you to Vegas. Properly that's an easy hop to Los Angeles (skepticism warranted because it's infrastructure in California), which gets you LA to Texas to Miami.
If they did it right, Texas ends up acting as the obvious central web that you can tie the country together with high speed rail over time.
We could build all of this for $400 billion perhaps, if it's done as it will be in Texas in terms of time & cost (enter the land & zoning nightmares in some parts of the country); $20b per year for 20 years (non inflation adjusted), which we can easily afford.