Bootstrap fixed points for self-hosting compilers prove a lot less in principle than some people seem to think. There's Trusting Trust's style of malicious fixed points where the compiler miscompiles everything but itself, but also trivial quine-style fixed points where the "compiler" can do nothing but reproduce itself. And a lot of practically relevant, non-trivial extensions of the quine example where the self-hosting compiler is seriously under-exercising its own use of the language.