Unless the tax credits are extended (and the likelihood of that was essentially zero already), Tesla is set to hit the phaseout point next year regardless, and will have them go to zero one year later. It's likely that if you reserve a Model 3 today, you won't get a tax credit when you take delivery. So that wouldn't change a whole lot. And assuming the subsidy is eliminated for everyone and not just Tesla, it'll make them more competitive.

I'd say the big danger for his stuff is SpaceX and NASA, and I don't think there's much risk there.