America is very big, and while passenger rail was a big thing into perhaps the 1970s, cheaper airfare and better airports allowed faster travel across such a wide expanse to take over. Most passenger rail was (and is) shared with freight, and track for heavy loads is built differently. Dedicated high speed rail on a nationwide scale would be astronomically expensive, especially here in the mountains where trestles and tunnels would need to be built from scratch.
I took Amtrak back east to my grandmother's funeral mainly because I refuse to fly. I simply will not accept the TSA porno-scanners and gate rape security theater. Driving that far would have taken too much time. Train is the way I would prefer to travel if the destination rather than the journey were my priority.
I don't know what to think of dedicated subways and light rail. I haven't really experienced it. The crowds one sees on TV repulse me, not because of new COVID fears, but because I like my personal space regardless. I completely understand the convenience and opportunity of urban life, but I don't think I fit there.