I mean... Why build HSR if u just have normal rail? It might get u from place A to B faster by an hour or so... What difference would that make?
Turns out it would make quite a lot of difference, right? Faster human transportation in history has always been a good thing.
As for the price, the assumption is that nuclear fusion and lunar mining are mature tech. That would certainly lower the price a lot, no?
Naah it's just a fun thought experiment lmao. Don't care about Mr. Douchebag.
As for the elevated rail thing- we would have to demolish A LOT of on ground infrastructure for that, no? Elevated makes sense for metros n stuff because of smaller turning radii. But for an absolutely straight tube? Ehhh.
Also, we need to factor in vertical turning radii as well, no? Elevation changes r quite drastic on the earth's surface. Building elevated means building crazy tall pillars and stuff (which also have to be earthquake resistant). Also, we would definitely need to build a lot of tunnels either ways (through hills, mountains, or simple plains whose elevation changes r too steep for our hypersonic vehicle)