Who said poor development environment. Emacs is a terrific lisp editor and straight sbcl (or any real lisp) is a better dev env than almost any other straight pl env.
Yeah, but that’s just complaining that just because we used to have flying cars we still should. We decided as a society to give up on flying cars. They’re gone. Move on with your (our) boring 2D lives.
I don’t think it’s fair to say that we’ve given up on Lisp machines because we chose to do so. Most people never got to experience them to begin with! Certainly not enough people to build as thorough a software ecosystem as we expect nowadays.