Is it "capitalism picking winners and losers but ... making taxpayers fund the losers" when the product is something that no one would otherwise make? How many nuclear reactors for moon-orbiting satellites would get built in the absence of national space programs funding them? For that matter, how many such satellites would get built, with or without nuclear reactors, if government space agencies weren't funding them?

That's an easy thing to overlook, but if you need a custom product, you have to pay someone to build it unless you build it yourself.