There's a lot of hand-waving and unrealistic beliefs in this piece with regard to costs. For example:

" O’Toole looks at the most expensive few lines possible:

Britain’s 345‐ mile London–Scotland HS2 high‐ speed rail line was originally projected to cost £32.7 billion (about $123 million per mile) and is currently expected to cost £106 billion ($400 million per mile).

International comparisons of high-speed rail costs exist, and Britain’s costs are by far the worst. "

It looks as if California will exceed that cost by quite a bit for it's equivalent length HSR project, if and when it's ever completed.

And how does this square with the current reality of the California project costs (estimated to be over $100M, even though it's over a decade for completion, and the budget has already grown >2.5x)

" the official Obama-era crayon, at 20,000 km, would be $500 billion at tunnel-free European costs, or maybe $600 billion with 5% tunneling "

So we're gonna do the rest of the 19,400 km for only $500bn, when the most recent 600km is costing $100bn?