> but why to ask California State for subsidy? Why not to build it using private funds?
Because you can't, in practice, acquire the rights of way necessary to build a substantial railroad/hyperloop/freeway or other major infrastructure project of that type without government (specifically, without use of eminent domain).
But as I recall, the gov't can use eminent domain to give land to a private entity if they're in favor of the idea for the "public good." Or am I way off base here...?
Because you can't, in practice, acquire the rights of way necessary to build a substantial railroad/hyperloop/freeway or other major infrastructure project of that type without government (specifically, without use of eminent domain).