If Trump cancels EV subsidies or pressures NASA to stop bankrolling SpaceX, Musk is basically fucked.
That is why Trump said that.
As with most giant corporations, if the government stopped heavily subsidizing them in many direct and many more indirect ways, they would basically collapse under their own incompetence quite quickly.
Its truly funny to watch libertarian types pretend they built their empires from the ground up, when the truth is that they basically always started from a very privileged background, more or less did shady things bordering on or actually being fraud, got some of their parent’s or parent’s friends to invest, and then grew further from massive government aid of one kind or another.