Taxpayer money is being diverted from services that are in dire need presently. That money is being used to privilege Musk and company to vast commonly owned underground land. In the past, fortunately still in some cases, companies were forced to pay the government for the externalities caused by the exclusive right to common land which deprives other tax payers of the same opportunity.
Curious, do you know the EROI difference for fossil fuels? How much difference is there in the opportunity cost? All energy is subsidized. Solar actually doesn't qualify for the subsidies oil does, same for electric cars. That's why they have a separate subsidy. Unlike oil's 15% the subsidy declines to 10% for solar and the EV car subsidy vanishes. All the things you mention can be covered by that 5% difference. That's opportunity cost.
Through avoiding externality payment due to the cost of "the tragedy of the commons" to the tax payer, as well as the massive subsidies to SolarCity, Tesla, and Space X. It is suspect to believe Hyperloop won't be massively subsidized as well, given his track record.
A subsidy, a tax cut, and an MLP walk into a bar. Each pays $5 for a draft beer. Each saved $1. The only difference is when they receive that $1. The punchline is thinking they're different.
Tesla doesn't benefit financially from the tax credits, they mostly benefit other automakers.
SpaceX doesn't have subsidies, it has contracts.
Elon Musk isn't any more reliant on subsidies than anyone else. How do you feel about the Koch brothers? They receive far more government assistance than Musk. Look anywhere else in the energy industry and you'll find more government assistance than what Elon receives.
