Yeah, I learned an enormous amount from it when I encountered it (in hard copy of course) in 01996, and some of what I learned is now no longer relevant.

There are some people building new Lisp machines: https://opencores.org/projects/igor https://github.com/lisper/cpus-caddr https://interlisp.org/ http://pt.withington.org/publications/LispM.html http://pt.withington.org/publications/VLM.html https://github.com/dseagrav/ld http://www.aviduratas.de/lisp/lispmfpga/ https://groups.google.com/g/comp.lang.lisp/c/36_qKNErHAg https://frank-buss.de/lispcpu/

Also, Morello includes some Lisp-machine-like features. In my view knowing about the history of hardware architectures is far more important for designing new ones than for reproducing old ones.