Yes, he's complaining about the abject failure of trains (and I have too). The project won't pay off if the same corruption that cost $105 billions results in an impractical project and that's the common result.
The US can't create an alternative to fossil fuels unless it solves it's inability to create public transit projects problem.
And if that money is not invested in trains, they only other suggestion practically speaking is, lets make highways bigger.
So yeah, I agree, you the US needs to get better at public infrastructure projects, but doing so while also working on trains, is better then doing so and building insane Texas highway cloverleaf interchanges.
If a nation pays a lot for a given infrastructure project because the nation is developing the means to produce it, then that nation would likely be able to produce the thing better later. Maybe that's Japan.
If a nation pays a lot for a given infrastructure project because corrupt interests have positioned themselves to soak up a lion's share of the money, there's no reason to think that won't happen the next time. That's what happens in the US. Further, thing about the US is that failed public transit project have become normal and accepted. Something is needed to change this but uncritically throwing money at them obviously won't be it.
$105 billion is about the size of California's current (and growing) surplus. Or about a fifth of how much California spent in 2021 ($512.8 billion). Yes it could be used to do more important things in the immediate sense but projects like these pay off tenfold in the long term