1) There are type 1/2/3 train operators that owns everything/borrows rails/owns just rails as Japanese laws classify them, but type 3 lines are mostly rural low-traffic branch lines. Most high-traffic lines are owned(+accesses leased to type 2s) by train operators. Some of regional Shinkansen lines are technically owned by government run JRTT agency and leased to local JR company, which are probably as unrelated as UK government and its Royal Mail are.

2) I mean, like, it's the place where the English loanword for "death by overwork" came from. Also, undervalued means things costing less than they are worth. Trash costing little isn't undervalued, that's more adequately valued.

Thank you, haha on answer 2 !!

Answer 1 is still not clear to me. Can you contrast it with how Spanish track is managed?

Shinkansen is built like a giant subway. Fixed transponders everywhere, mission control monitoring and coordinating everything, stations right on the main line etc etc. They even use the same callouts as intra-city trains and they've long been at almost GoA 2 levels in train people terms?

I admit that I was a bit uninformed about specifics of Spanish train system in that, the rails were in fact laid by then-Spanish national rail and the operator was then-national company, but still, they don't seem like built and maintained like the BART or the NYC subway that happens to go 200mph in straight sections. That Shinkansen architecture is unique, and that is also guaranteed to be more labor intensive than how everything in most HSRs are.