> Also if you make hardware absolutely optomised for Lisp then all the C, FORTRAN, and Cobol (this was the 1970's!) programmers aren't particularly interested because it does nothing for their code.
Yes, but it's different now. Now our programming languages are closer to lisp than C. We use javascript, python, ruby, haskell and throw functions all over the place and they come with a cost of frames etc. Even "low level" languages like C++ and Java recently gained powerful capabilities to express lambdas, and C++ programmers use lambdas and std::function pretty often. Why not experiment with a machine that can handle function passing better Turing machines. It seems like if you use enough high-level structures in your code, even a "slower" lisp machine can run your faster than "fast" classical Turing-machine-like-CPU.
This is not even for general purpose CPUs. There are embedded devices people write python or javascript code on. Why not make those CPUs lisp machines?